CYCLIC SULFAMIDE COMPOUNDS AND METHODS OF USING SAME

Abstract

The present disclosure provides, in part, cyclic sulfamide compounds, and pharmaceutical compositions thereof, useful as modulators of Hepatitis B (HBV) core protein, and methods of treating Hepatitis B (HBV) infection.

Description

RELATED APPLICATIONS

This application claims priority to and the benefit of U.S. provisional application No. 62/465,986, filed Mar. 2, 2017, U.S. provisional application No. 62/529,874 filed Jul. 7, 2017, and U.S. provisional application No. 62/549,728 filed Aug. 24, 2017, each of which is incorporated by reference in its entirety.

BACKGROUND

Hepatitis B (HBV) causes viral hepatitis that can further lead to chronic liver disease and increase the risk of liver cirrhosis and liver cancer (hepatocellular carcinoma). Worldwide, about 2 billion people have been infected with HBV, around 360 million people are chronically infected, and every year HBV infection causes more than one half million deaths. HBV can be spread by body fluids: from mother to child, by sex, and via blood products. Children born to HBV-positive mothers may also be infected, unless vaccinated at birth.

The hepatitis virus particle is composed of a lipid envelope studded with surface protein (HBsAg) that surrounds the viral core. The core is composed of a protein shell, or capsid, built of 120 core protein (Cp) dimers, which in turn contains the relaxed circular DNA (rcDNA) viral genome as well as viral and host proteins. In an infected cell, the genome is found as a covalently closed circular DNA (cccDNA) in the host cell nucleus. The cccDNA is the template for viral RNAs and thus viral proteins. In the cytoplasm, Cp assembles around a complex of full-length viral RNA (the so-called pregenomic RNA or pgRNA and viral polymerase (P). After assembly, P reverse transcribes the pgRNA to rcDNA within the confines of the capsid to generate the DNA-filled viral core.

At present, chronic HBV is primarily treated with nucleotide analogs (e.g., entecavir) that suppress the virus while the patient remains on treatment, but do not eliminate the infection, even after many years of treatment. Once a patient starts taking nucleotide analogs, most must continue taking them or risk the possibility of a life threatening immune response due to viral rebound. Further, nucleotide therapy may lead to the emergence of antiviral drug resistance.

The only FDA approved alternative to nucleotide analogs is treatment with interferon α or pegylated interferon α. Unfortunately, the adverse event incidence and profile of interferon α can result in poor tolerability, and many patients are unable to complete therapy. Moreover, only a small percentage of patients are considered appropriate for interferon therapy, as only a small subset of patients are likely to have a sustained clinical response to a course of interferon therapy. As a result, interferon-based therapies are used in only a small percentage of all diagnosed patients who elect treatment.

Thus, current HBV treatments can range from palliative to watchful waiting. Nucleotide analogs suppress virus production, treating the symptom, but leave the infection intact. Interferon α has severe side effects and less tolerability among patients and is successful as a finite treatment strategy in only a small minority of patients. There is a clear on-going need for more effective treatments for HBV infections.

SUMMARY

The present disclosure provides, in part, cyclic sulfamide compounds and pharmaceutical compositions thereof, useful for modulation of HBV core protein, and methods of treating HBV infections.

In one aspect, the disclosure provides compounds of Formula I:

or a pharmaceutically acceptable salt thereof, where the variables are described in the detailed description.

In another aspect, the disclosure provides pharmaceutical compositions comprising a compound of Formula I, or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable excipient.

In another aspect, the disclosure provides a method of treating HBV infection in a subject in need thereof comprising: administering to the subject an effective amount of compound of Formula I, or a pharmaceutically acceptable salt thereof.

In another aspect, the disclosure provides a method of treating HBV infection in a subject in need thereof comprising: administering to the subject a pharmaceutical composition comprising a compound of Formula I, or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable excipient.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is the crystal structure of HBV-CSU-016-ISO-I as described herein.

DETAILED DESCRIPTION

The features and other details of the disclosure will now be more particularly described. Before further description of the present disclosure, certain terms employed in the specification, examples and appended claims are collected here. These definitions should be read in light of the remainder of the disclosure and as understood by a person of skill in the art. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by a person of ordinary skill in the art.

Definitions

“Treating” includes any effect, e.g., lessening, reducing, modulating, or eliminating, that results in the improvement of the condition, disease, disorder and the like.

The term “alkenyl” as used herein refers to an unsaturated straight or branched hydrocarbon having at least one carbon-carbon double bond. Exemplary alkenyl groups include, but are not limited to, a straight or branched group of 2-6 or 3-4 carbon atoms, referred to herein as C_2-6alkenyl, and C_3-4alkenyl, respectively. Exemplary alkenyl groups include, but are not limited to, vinyl, allyl, butenyl, pentenyl, etc.

The term “alkoxy” as used herein refers to a straight or branched alkyl group attached to oxygen (alkyl-O—). Exemplary alkoxy groups include, but are not limited to, alkoxy groups of 1-6 or 2-6 carbon atoms, referred to herein as C_1-6alkoxy, and C_2-6alkoxy, respectively. Exemplary alkoxy groups include, but are not limited to methoxy, ethoxy, isopropoxy, etc.

The term “alkoxyalkyl” as used herein refers to an alkyl group substituted with an alkoxy group. Examples include but are not limited to CH₃CH₂OCH₂—, CH₃OCH₂CH₂— and CH₃OCH₂—.

The term “alkyl” as used herein refers to a saturated straight or branched hydrocarbon. Exemplary alkyl groups include, but are not limited to, straight or branched hydrocarbons of 1-6, 1-4, or 1-3 carbon atoms, referred to herein as C_1-6alkyl, C_1-4alkyl, and C_1-3alkyl, respectively. Exemplary alkyl groups include, but are not limited to, methyl, ethyl, propyl, isopropyl, 2-methyl-1-butyl, 3-methyl-2-butyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl, 2-methyl-2-pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 2,2-dimethyl-1-butyl, 3,3-dimethyl-1-butyl, 2-ethyl-1-butyl, butyl, isobutyl, t-butyl, pentyl, isopentyl, neopentyl, hexyl, etc.

The term “alkynyl” as used herein refers to an unsaturated straight or branched hydrocarbon having at least one carbon-carbon triple bond. Exemplary alkynyl groups include, but are not limited to, straight or branched groups of 2-6, or 3-6 carbon atoms, referred to herein as C_2-6alkynyl, and C_3-6alkynyl, respectively. Exemplary alkynyl groups include, but are not limited to, ethynyl, propynyl, butynyl, pentynyl, hexynyl, methylpropynyl, etc.

The term “carbonyl” as used herein refers to the radical —C(O)—.

The term “cyano” as used herein refers to the radical —CN.

The terms “cycloalkyl” or a “carbocyclic group” as used herein refers to a saturated or partially unsaturated hydrocarbon group of, for example, 3-6, or 4-6 carbons, referred to herein as C_3-6cycloalkyl or C_4-6cycloalkyl, respectively. Exemplary cycloalkyl groups include, but are not limited to, cyclohexyl, cyclopentyl, cyclopentenyl, cyclobutyl or cyclopropyl.

The terms “halo” or “halogen” as used herein refer to F, Cl, Br, or I.

The term “haloalkyl” as used herein refers to an alkyl group substituted with one or more halogen atoms. Examples include but are not limited to —CH₂F, —CHCl₂, —CF₃, —CH₂CF₃, —CF₂CH₃, CCl₂CF₃ and —CF₂CF₃.

The term “haloalkoxy” as used herein refers to an alkoxy group substituted with one or more halogen atoms. Examples include but are not limited to CF₃—O—, CF₃CH₂—O—, and CF₃CF₂—O—.

The terms “heteroaryl” or “heteroaromatic group” as used herein refers to a monocyclic aromatic 5-6 membered ring system or bicyclic aromatic 8-12 membered ring system containing one or more heteroatoms, for example one to three heteroatoms, such as nitrogen, oxygen, and sulfur. Where possible, said heteroaryl ring may be linked to the adjacent radical though carbon or nitrogen. Examples of 5-6 membered monocyclic heteroaryls include but are not limited to: furanyl, thiophenyl (also referred to as thienyl), pyrrolyl, thiazolyl, oxazolyl, isothiazolyl, isoxazolyl, imidazolyl, pyrazolyl, 1H-1,2,3-triazolyl, 2H-1,2,3-triazolyl, 1,2,4-triazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, 1,3,5-triazinyl, 1,2,4-triazinyl, 1,2,3-triazinyl, 1,2,4-oxadiazolyl, 1,3,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,2,4-thiadiazolyl, 1,3,4-thiadiazolyl, and 1,2,5-thiadiazolyl. Examples of 8-12 membered bicyclic heteroaryls include but are not limited to: benzofuranyl, isobenzofuranyl, benzo[b]thiophenyl, benzo[c]thiophenyl, indolyl, isoindolyl, benzo[d]isoxazolyl, benzo[c]isoxazolyl, benzo[d]oxazolyl, benzo[d]isothiazolyl, benzo[c]isothiazolyl, benzo[d]thiazolyl, indazolyl, benzo[d]imidazolyl, benzo[d]imidazolyl, and benzo[d][1,2,3]triazolyl.

The terms “heterocyclyl” or “heterocyclic group” are art-recognized and refer to saturated or partially unsaturated 4-7 membered ring structures, whose ring structures include one to three heteroatoms, such as nitrogen, oxygen, and sulfur. Where possible, heterocyclyl rings may be linked to the adjacent radical through carbon or nitrogen. Examples of heterocyclyl groups include, but are not limited to, pyrrolidinyl, piperidinyl, morpholinyl, thiomorpholinyl, piperazinyl, oxetanyl, azetidinyl, tetrahydrofuranyl or dihydrofuranyl etc.

The terms “hydroxy” and “hydroxyl” as used herein refers to the radical —OH.

The term “hydroxyalkyl” as used herein refers to an alkyl group substituted with one or more hydroxy groups. Examples include but are not limited to HOCH₂—, HOCH₂CH₂— and CH₃CH(OH)CH₂—.

The term “hydroxyalkoxy” as used herein refers to an alkoxy group substituted with one or more hydroxy groups. Examples include but are not limited to HOCH₂—O—, HOCH₂CH₂—O— and CH₃CH(OH)CH₂—O—.

The term “R^aR^bN—C_1-6alkyl-,” as used herein refers to an alkyl group substituted with a R^aR^bN— group, as defined herein. Examples include but are not limited to NH₂CH₂—, NH(CH₃)CH₂—, N(CH₃)₂CH₂CH₂— and CH₃CH(NH₂)CH₂—.

The term “R^aR^bN—C_1-6alkoxy,” as used herein refers to an alkoxy group substituted with one or more R^aR^bN— groups, as defined herein. Examples include but are not limited to NH₂CH₂—, NH(CH₃)CH₂—O—, N(CH₃)₂CH₂CH₂—O— and CH₃CH(NH₂)CH₂—O—.

The term “oxo” as used herein refers to the radical ═O.

“Pharmaceutically acceptable” include molecular entities and compositions that do not produce an adverse, allergic or other untoward reaction when administered to an animal, or a human, as appropriate. For human administration, preparations should meet sterility, pyrogenicity, and general safety and purity standards as required by FDA Office of Biologics standards.

The term “pharmaceutically acceptable carrier” or “pharmaceutically acceptable excipient” as used herein refers to any and all solvents, dispersion media, coatings, isotonic and absorption delaying agents, and the like, that are compatible with pharmaceutical administration. The use of such media and agents for pharmaceutically active substances is well known in the art. The compositions may also contain other active compounds providing supplemental, additional, or enhanced therapeutic functions.

The term “pharmaceutical composition” as used herein refers to a composition comprising at least one compound as disclosed herein formulated together with one or more pharmaceutically acceptable excipients.

“Individual,” “patient,” or “subject” are used interchangeably and include any animal, including mammals, preferably mice, rats, other rodents, rabbits, dogs, cats, swine, cattle, sheep, horses, or primates, and most preferably humans. The compounds or pharmaceutical compositions of the disclosure can be administered to a mammal, such as a human, but can also be administered to other mammals such as an animal in need of veterinary treatment, e.g., domestic animals (e.g., dogs, cats, and the like), farm animals (e.g., cows, sheep, pigs, horses, and the like) and laboratory animals (e.g., rats, mice, guinea pigs, and the like). The mammal treated in the methods of the disclosure is desirably a mammal in which treatment of HBV infection is desired. “Modulation” includes antagonism (e.g., inhibition), agonism, partial antagonism and/or partial agonism.

The term “therapeutically effective amount” or “effective amount” as used herein refers to the amount of the subject compound that will elicit the biological or medical response of a tissue, system or animal, (e.g. mammal or human) that is being sought by the researcher, veterinarian, medical doctor or other clinician. The compounds or pharmaceutical compositions of the disclosure are administered in therapeutically effective amounts to treat a disease. Alternatively, a therapeutically effective amount of a compound is the quantity required to achieve a desired therapeutic and/or prophylactic effect.

The term “pharmaceutically acceptable salt(s)” as used herein refers to salts of acidic or basic groups that may be present in compounds used in the compositions. Compounds included in the present compositions that are basic in nature are capable of forming a wide variety of salts with various inorganic and organic acids. The acids that may be used to prepare pharmaceutically acceptable acid addition salts of such basic compounds are those that form non-toxic acid addition salts, i.e., salts containing pharmacologically acceptable anions, including, but not limited to, malate, oxalate, chloride, bromide, iodide, nitrate, sulfate, bisulfate, phosphate, acid phosphate, isonicotinate, acetate, lactate, salicylate, citrate, tartrate, oleate, tannate, pantothenate, bitartrate, ascorbate, succinate, maleate, gentisinate, fumarate, gluconate, glucaronate, saccharate, formate, benzoate, glutamate, methanesulfonate, ethanesulfonate, benzenesulfonate, p-toluenesulfonate and pamoate (i.e., 1,1′-methylene-bis-(2-hydroxy-3-naphthoate)) salts. Compounds included in the present compositions that are acidic in nature are capable of forming base salts with various pharmacologically acceptable cations. Examples of such salts include alkali metal or alkaline earth metal salts, particularly calcium, magnesium, sodium, lithium, zinc, potassium, and iron salts. Compounds included in the present compositions that include a basic or acidic moiety may also form pharmaceutically acceptable salts with various amino acids. The compounds of the disclosure may contain both acidic and basic groups; for example, one amino and one carboxylic acid group. In such a case, the compound can exist as an acid addition salt, a zwitterion, or a base salt.

The compounds of the disclosure may contain one or more chiral centers and, therefore, exist as stereoisomers. The term “stereoisomers” when used herein consist of all enantiomers or diastereomers. These compounds may be designated by the symbols “(+),” “(−),” “R” or “S,” depending on the configuration of substituents around the stereogenic carbon atom, but the skilled artisan will recognize that a structure may denote a chiral center implicitly. The present disclosure encompasses various stereoisomers of these compounds and mixtures thereof. Mixtures of enantiomers or diastereomers may be designated “(±)” in nomenclature, but the skilled artisan will recognize that a structure may denote a chiral center implicitly.

The compounds of the disclosure may contain one or more double bonds and, therefore, exist as geometric isomers resulting from the arrangement of substituents around a carbon-carbon double bond. The symbol denotes a bond that may be a single, double or triple bond as described herein. Substituents around a carbon-carbon double bond are designated as being in the “Z” or “E” configuration wherein the terms “Z” and “E” are used in accordance with IUPAC standards. Unless otherwise specified, structures depicting double bonds encompass both the “E” and “Z” isomers. Substituents around a carbon-carbon double bond alternatively can be referred to as “cis” or “trans,” where “cis” represents substituents on the same side of the double bond and “trans” represents substituents on opposite sides of the double bond.

Compounds of the disclosure may contain a carbocyclic or heterocyclic ring and therefore, exist as geometric isomers resulting from the arrangement of substituents around the ring. The arrangement of substituents around a carbocyclic or heterocyclic ring are designated as being in the “Z” or “E” configuration wherein the terms “Z” and “E” are used in accordance with IUPAC standards. Unless otherwise specified, structures depicting carbocyclic or heterocyclic rings encompass both “Z” and “E” isomers. Substituents around a carbocyclic or heterocyclic rings may also be referred to as “cis” or “trans”, where the term “cis” represents substituents on the same side of the plane of the ring and the term “trans” represents substituents on opposite sides of the plane of the ring. Mixtures of compounds wherein the substituents are disposed on both the same and opposite sides of plane of the ring are designated “cis/trans.”

Individual enantiomers and diasteriomers of compounds of the present disclosure can be prepared synthetically from commercially available starting materials that contain asymmetric or stereogenic centers, or by preparation of racemic mixtures followed by resolution methods well known to those of ordinary skill in the art. These methods of resolution are exemplified by (1) attachment of a mixture of enantiomers to a chiral auxiliary, separation of the resulting mixture of diastereomers by recrystallization or chromatography and liberation of the optically pure product from the auxiliary, (2) salt formation employing an optically active resolving agent, (3) direct separation of the mixture of optical enantiomers on chiral liquid chromatographic columns or (4) kinetic resolution using stereoselective chemical or enzymatic reagents. Racemic mixtures can also be resolved into their component enantiomers by well known methods, such as chiral-phase liquid chromatography or crystallizing the compound in a chiral solvent. Stereoselective syntheses, a chemical or enzymatic reaction in which a single reactant forms an unequal mixture of stereoisomers during the creation of a new stereocenter or during the transformation of a pre-existing one, are well known in the art. Stereoselective syntheses encompass both enantio- and diastereoselective transformations, and may involve the use of chiral auxiliaries. For examples, see Carreira and Kvaerno, Classics in Stereoselective Synthesis, Wiley-VCH: Weinheim, 2009.

The compounds disclosed herein can exist in solvated as well as unsolvated forms with pharmaceutically acceptable solvents such as water, ethanol, and the like, and it is intended that the disclosure embrace both solvated and unsolvated forms. In one embodiment, the compound is amorphous. In one embodiment, the compound is a single polymorph. In another embodiment, the compound is a mixture of polymorphs. In another embodiment, the compound is in a crystalline form.

The disclosure also embraces isotopically labeled compounds of the disclosure which are identical to those recited herein, except that one or more atoms are replaced by an atom having an atomic mass or mass number different from the atomic mass or mass number usually found in nature. Examples of isotopes that can be incorporated into compounds of the disclosure include isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorus, sulfur, fluorine and chlorine, such as ²H, ³H, ¹³C, ¹⁴C, ¹⁵N, ¹⁸O, ¹⁷O, ³¹P, ³²P, ³⁵S, ¹⁸F, and ³⁶Cl, respectively. For example, a compound of the disclosure may have one or more H atom replaced with deuterium.

Certain isotopically-labeled disclosed compounds (e.g., those labeled with ³H and ¹⁴C) are useful in compound and/or substrate tissue distribution assays. Tritiated (i.e., ³H) and carbon-14 (i.e., ¹⁴C) isotopes are particularly preferred for their ease of preparation and detectability. Further, substitution with heavier isotopes such as deuterium (i.e., ²H) may afford certain therapeutic advantages resulting from greater metabolic stability (e.g., increased in vivo half-life or reduced dosage requirements) and hence may be preferred in some circumstances. Isotopically labeled compounds of the disclosure can generally be prepared by following procedures analogous to those disclosed in the examples herein by substituting an isotopically labeled reagent for a non-isotopically labeled reagent.

The term “prodrug” refers to compounds that are transformed in vivo to yield a disclosed compound or a pharmaceutically acceptable salt, hydrate or solvate of the compound. The transformation may occur by various mechanisms (such as by esterase, amidase, phosphatase, oxidative and or reductive metabolism) in various locations (such as in the intestinal lumen or upon transit of the intestine, blood or liver). Prodrugs are well known in the art (for example, see Rautio, Kumpulainen, et al, Nature Reviews Drug Discovery 2008, 7, 255). For example, if a compound of the disclosure or a pharmaceutically acceptable salt, hydrate or solvate of the compound contains a carboxylic acid functional group, a prodrug can comprise an ester formed by the replacement of the hydrogen atom of the acid group with a group such as (C_1-8)alkyl, (C_2-12)alkylcarbonyloxymethyl, 1-(alkylcarbonyloxy)ethyl having from 4 to 9 carbon atoms, 1-methyl-1-(alkylcarbonyloxy)-ethyl having from 5 to 10 carbon atoms, alkoxycarbonyloxymethyl having from 3 to 6 carbon atoms, 1-(alkoxycarbonyloxy)ethyl having from 4 to 7 carbon atoms, 1-methyl-1-(alkoxycarbonyloxy)ethyl having from 5 to 8 carbon atoms, N-(alkoxycarbonyl)aminomethyl having from 3 to 9 carbon atoms, 1-(N-(alkoxycarbonyl)amino)ethyl having from 4 to 10 carbon atoms, 3-phthalidyl, 4-crotonolactonyl, gamma-butyrolacton-4-yl, di-N,N—(C_1-2)alkylamino(C_2-3)alkyl (such as β-dimethylaminoethyl), carbamoyl-(C_1-2)alkyl, N,N-di(C_1-2)alkylcarbamoyl-(C_1-2)alkyl and piperidino-, pyrrolidino- or morpholino(C_2-3)alkyl.

I. Cyclic Sulfamide Compounds

In one aspect, the disclosure provides a compound of Formula I:

or a pharmaceutically acceptable salt thereof, wherein:

R¹ is selected from the group consisting of phenyl, naphthyl, and 5-6 membered monocyclic or 8-12 membered bicyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, wherein the phenyl, naphthyl, and heteroaryl may be optionally substituted with one, two, or three substituents independently selected from the group consisting of halogen, —OH, —CN, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, haloC_1-6alkyl, C_1-6alkoxy, haloC_1-6alkoxy, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl, wherein q is 0, 1, or 2, wherein t is 1 or 2;

R² is hydrogen or C_1-6alkyl;

R³ is selected from the group consisting of 5-6 membered monocyclic or 8-12 membered bicyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S; phenyl; C_1-6alkyl; and C_3-6cycloalkyl, wherein the heteroaryl, phenyl, C_1-6alkyl, and C_3-6cycloalkyl may be optionally substituted with one or two substituents independently selected from the group consisting of: halogen, —OH, —CN, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_1-6haloalkyl, C_1-6alkoxy, haloC_1-6alkoxy, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, —C(O)O—C_1-6alkyl, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl, imidazolyl, triazolyl, phenyl, pyridyl, and pyrimidinyl, wherein the thienyl, thiazolyl, pyrazolyl, imidazolyl, triazolyl, phenyl, pyridyl and pyrimidinyl are optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, hydroxyC_1-4alkyl, C_1-4alkoxy and C_1-4alkylsulfonylamino, wherein q is 0, 1, or 2, wherein t is 1 or 2;

R⁴ is hydrogen or C_1-6alkyl optionally substituted with one, two, or three substituents independently selected from the group consisting of halogen, —OH, —CN, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_2-6alkenyl, C_2-6alkynyl, C_1-6haloalkyl, C_1-6alkoxy, haloC_1-6alkoxy, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, formyl, —C(O)OH, a-C(O)O—C_1-6alkyl, benzyloxy, C_1-4alkoxyphenyl, pyrrolidinyl, morpholinyl, tetrahydrofuranyl and triazolyl, wherein q is 0, 1, or 2, wherein t is 1 or 2;

R⁵ is hydrogen or C_1-6alkyl optionally substituted with a substituent selected from the group consisting of halogen, —OH, C_1-6alkoxy, —NR^aR^b, and R^aR^bN—C_1-4alkyl;

R⁶ is hydrogen or C_1-6alkyl;

R^a and R^b are independently hydrogen or C_1-6alkyl; or

R^a and R^b may be taken together with the nitrogen to which R^a and R^b are attached to form:

R^c is hydrogen or C_1-6alkyl; and

w is 1 or 2.

In certain embodiments, R³ is a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N and S, optionally substituted with one, two, or three substituents independently selected from the group consisting of: halogen, —OH, —CN, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, haloC_1-6alkyl, C_1-6alkoxy, haloC_1-6alkoxy, —C(O)NR^aR^b, —C(O)OH, —C(O)O—C_1-6alkyl, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl, imidazolyl, triazolyl, phenyl, pyridyl, and pyrimidinyl, wherein the thienyl, thiazolyl, pyrazolyl, imidazolyl, triazolyl, phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, hydroxyC_1-4alkyl, C_1-4alkoxy and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is furanyl, thienyl, pyrazolyl, isoxazolyl, thiazolyl, isothiazolyl, or 1,3,4-thiadiazolyl, each of which is optionally substituted with one or two substituents independently selected from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl or hydroxyC_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, triazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is selected from the group consisting of:

wherein:

R³³ is selected from the group consisting of: hydrogen, halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, triazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino;

R^33a is hydrogen, halo or C_1-4alkyl;

R³⁴ is selected from the group consisting of hydrogen and C_1-4alkyl; and

R³⁵, R³⁶ and R³⁷ are independently selected from the group consisting of hydrogen, halo, hydroxy, cyano, carboxy, carbamoyl, haloC_1-4alkyl, C_1-4alkoxy, haloC_1-4alkoxy, carboxyC_1-4alkoxy, R^aR^bN—C_1-4alkoxy, C_1-4alkoxycarbonyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl, and imidazolyl optionally substituted with C_1-4alkyl.

In certain embodiments, R³ is

wherein R³⁵, R³⁶ and R³⁷ are independently selected from the group consisting of hydrogen, halo, hydroxy, cyano, carboxy, carbamoyl, haloC_1-4alkyl, C_1-4alkoxy, haloC_1-4alkoxy, carboxyC_1-4alkoxy, R^aR^bN—C_1-4alkoxy, C_1-4alkoxycarbonyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl, and imidazolyl optionally substituted with C_1-4alkyl.

In certain embodiments, R³ is

wherein R³³ is selected from the group consisting of: hydrogen, halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl or hydroxyC_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is:

wherein R³³ is selected from the group consisting of: hydrogen, halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl or hydroxyC_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is:

wherein R³³ is selected from the group consisting of: hydrogen, halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl or hydroxyC_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is:

wherein: R³³ is selected from the group consisting of: hydrogen, halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, pyrazolyl optionally substituted with C_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is:

wherein: R³³ is selected from the group consisting of: hydrogen, halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is:

wherein: R³³ is selected from the group consisting of hydrogen, halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments:

w is 2;

R¹ is phenyl optionally substituted with one to three substituents independently selected from the group consisting of halo, cyano, C_1-4alkyl and haloC_1-4alkyl;

R² is hydrogen;

R³ is C_1-4alkyl, C_3-6cycloalkyl,

furanyl, thienyl, thiazolyl, pyrazolyl, imidazolyl, isoxazolyl, thiazolyl, isothiazolyl, or 1,3,4-thiadiazolyl, each of which is optionally substituted with one or two substituents independently selected from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, thienyl, thiazolyl, pyrazolyl optionally substituted with one two or three substituents independently selected from C_1-4alkyl and hydroxyC_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, triazolyl optionally substituted with C_1-4alkyl, benzyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino,

phenyl or pyridinyl, each or which is optionally substituted with one, two or three substituents independently selected from the group consisting of halo, hydroxy, cyano, carboxy, carbamoyl, haloC_1-4alkyl, C_1-4alkoxy, haloC_1-4alkoxy, carboxyC_1-4alkoxy, R^aR^bN—C_1-4alkoxy, 1-methylpyrazolyl, C_1-4alkoxycarbonyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl, and imidazolyl optionally substituted with C_1-4alkyl;

R⁴ is hydrogen, C_2-6alkenyl, C_2-6alkynyl, C_1-4alkyl optionally substituted with hydroxy, cyano, C_1-4alkoxy, haloC_1-4alkoxy, C_1-4alkylsulfonyl, R^aR^bN—, formyl carboxy, carbamoyl, benzyloxy, C_1-4alkoxyphenyl, pyrrolidinyl, morpholinyl, tetrahydrofuranyl or triazolyl;

R⁵ is hydrogen, C_1-4alkyl, C_1-4alkoxy, or R^aR^bN—C_1-4alkyl;

R⁶ is hydrogen; and

R^a and R^b are independently hydrogen or C_1-4alkyl.

In certain embodiments:

w is 2;

R¹ is phenyl optionally substituted with one to three substituents independently selected from the group consisting of halo, cyano, C_1-4alkyl and haloC_1-4alkyl;

R² is hydrogen;

R³ is furanyl, thienyl, or thiazolyl, each of which is optionally substituted with one or two substituents independently selected from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl or hydroxC_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, benzyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy and C_1-4alkylsulfonylamino,

phenyl or pyridinyl, each or which is optionally substituted with one to three substituents independently selected from the group consisting of halo, hydroxy, cyano, carboxy, carbamoyl, haloC_1-4alkyl, C_1-4alkoxy, haloC_1-4alkoxy, carboxyC_1-4alkoxy, R^aR^bN—C_1-4alkoxy, C_1-4alkoxycarbonyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl, and imidazolyl optionally substituted with C_1-4alkyl;

R⁴ is hydrogen, C_2-6alkenyl, C_2-6alkynyl, C_1-4alkyl optionally substituted with hydroxy, cyano, C_1-4alkoxy, haloC_1-4alkoxy, C_1-4alkylsulfonyl, R^aR^bN—, carboxy, carbamoyl, benzyloxy, formyl, C_1-4alkoxyphenyl, pyrrolidinyl, morpholinyl, tetrahydrofuranyl or triazolyl;

R⁵ is hydrogen, C_1-4alkyl, C_1-4alkoxy, or R^aR^bN—C_1-4alkyl;

R⁶ is hydrogen; and

R^a and R^b are independently hydrogen or C_1-4alkyl.

In certain embodiments:

w is 2;

R¹ is phenyl optionally substituted with one to three substituents independently selected from the group consisting of halo, cyano, C_1-4alkyl and haloC_1-4alkyl;

R² is hydrogen;

R³ is C_1-4alkyl, C_3-6cycloalkyl,

furanyl, isoxazolyl, isothiazolyl, pyrazolyl, pyridinyl or 1,3,4-thiadiazolyl, each of which is optionally substituted with halo, C_1-4alkyl or phenyl,

thiazolyl optionally substituted with one or two substituents independently selected from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, thienyl, thiazolyl, pyrazolyl, 1-methylpyrazolyl, pyridinyl optionally substituted with halo, and phenyl optionally substituted with one or two substituents independently selected from the group consisting of halo and C_1-4alkoxy,

thienyl optionally substituted with one or two substituents independently selected from the group consisting of: halo, C_1-4alkyl, R^aR^bN—C_1-4alkoxy, thienyl, pyrimidinyl, pyrazolyl, 1-methylpyrazolyl, benzyl, pyridinyl optionally substituted with halo or haloC_1-4alkyl, and phenyl optionally substituted with one or two substituents independently selected from the group consisting of halo, cyano, C_1-4alkoxy, haloC_1-4alkyl and C_1-4alkylsulfonylamino, or

phenyl optionally substituted with one to three substituents independently selected from the group consisting of: halo, hydroxy, cyano, carboxy, carbamoyl, haloC_1-4alkyl, C_1-4alkoxy, haloC_1-4alkoxy, carboxyC_1-4alkoxy, R^aR^bN—C_1-4alkoxy, 1-methylpyrazolyl and C_1-4alkoxycarbonyl;

R⁴ is hydrogen, C_2-6alkenyl, C_2-6alkynyl, C_1-4alkyl optionally substituted with hydroxy, cyano, C_1-4alkoxy, haloC_1-4alkoxy, C_1-4alkylsulfonyl, carboxy, carbamoyl, benzyloxy, formyl, C_1-4alkoxyphenyl, pyrrolidinyl, morpholinyl, tetrahydrofuranyl or triazolyl;

R⁵ is hydrogen, C_1-4alkyl, C_1-4alkoxy, or R^aR^bN—C_1-4alkyl;

R⁶ is hydrogen; and

R^a and R^b are independently hydrogen or C_1-4alkyl.

In certain embodiments, R³ is C_1-6alkyl or C_3-6cycloalkyl, wherein the C_1-6alkyl or C_3-6cycloalkyl is optionally substituted with one, two, or three substituents independently selected from the group consisting of: halogen, —OH, —CN, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_1-6haloalkyl, C_1-6alkoxy, C_1-6haloalkoxy, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, —C(O)O—C_1-6alkyl, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl, imidazolyl, triazolyl, phenyl, pyridyl, and pyrimidinyl, wherein the thienyl, thiazolyl, pyrazolyl, imidazolyl, triazolyl, phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, hydroxyC_1-4alkyl, C_1-4alkoxy and C_1-4alkylsulfonylamino, wherein q is 0, 1, or 2, and wherein t is 1 or 2.

In certain embodiments, R³ is C_1-6alkyl or C_3-6cycloalkyl.

In another aspect, the disclosure provides a compound of Formula I:

or a pharmaceutically acceptable salt thereof, wherein:

R¹ is selected from the group consisting of phenyl, naphthyl, and 5-6 membered monocyclic or 8-12 membered bicyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, wherein the phenyl, naphthyl, and heteroaryl may be optionally substituted with one, two, or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl;

R² is hydrogen or C_1-6alkyl optionally substituted with a substituent selected from the group consisting of halogen, —OH, C_1-6alkoxy, —NR^aR^b, and R^aR^bN—C_1-6alkyl;

R³ is selected from the group consisting of 5-6 membered monocyclic or 8-12 membered bicyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S; phenyl; C_1-6alkyl; and C_3-6cycloalkyl, wherein the heteroaryl, phenyl, C_1-6alkyl, and C_3-6cycloalkyl are optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl, C_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl, phenyl, and a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, wherein the phenyl or 5-6 membered monocyclic heteroaryl is optionally substituted with one, two or three substituents independently selected from the group consisting of halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl;

R⁴ is hydrogen or C_1-6alkyl optionally substituted with one, two, or three substituents independently selected from the group consisting of halogen, —OH, —CN, —S(O)_q—C_1-6alkyl, —NR^aR^b, —S(O)_t—NR^aR^b, C_2-6alkenyl, C_2-6alkynyl, haloC_1-6alkyl, C_1-6alkoxy, haloC_1-6alkoxy, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, formyl, —C(O)OH, a-C(O)O—C_1-6alkyl, benzyloxy, C_1-4alkoxyphenyl, pyrrolidinyl, morpholinyl, tetrahydrofuranyl and triazolyl;

R⁵ is hydrogen or C_1-6alkyl optionally substituted with a substituent selected from the group consisting of halogen, —OH, C_1-6alkoxy, —NR^aR^b, and R^aR^bN—C_1-6alkyl;

R⁶ is hydrogen, halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl;

R^a and R^b are independently hydrogen or C_1-6alkyl; or

R^a and R^b may be taken together with the nitrogen to which R^a and R^b are attached to form:

R^c is hydrogen or C_1-6alkyl;

for each occurrence, q is 0, 1 or 2;

for each occurrence, t is 1 or 2; and

w is 1 or 2;

with the provisos that:

• • when R³ is thiophen-2-yl or furan-2-yl, the thiophen-2-yl or furan-2-yl is substituted with at least one substituent;
  • when R³ is pyrazol-4-yl, the pyrazol-4-yl is substituted with at least one substituent other than C_1-6alkyl; and
  • when R³ is phenyl, the phenyl is substituted with at least one substituent other than halo and C_1-6alkoxy.

In certain embodiments, the 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, is selected from the group consisting of: furanyl, thienyl, pyrrolyl, thiazolyl, oxazolyl, isothiazolyl, isoxazolyl, imidazolyl, pyrazolyl, 1H-1,2,3-triazolyl, 2H-1,2,3-triazolyl, 1,2,4-triazolyl, pyridinyl pyridazinyl, pyrimidinyl, pyrazinyl, 1,3,5-triazinyl, 1,2,4-triazinyl, 1,2,3-triazinyl, 1,2,4-oxadiazolyl, 1,3,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,2,4-thiadiazolyl, 1,3,4-thiadiazolyl and 1,2,5-thiadiazolyl.

In certain embodiments, the 8-12 membered bicyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, is selected from the group consisting of: benzofuranyl, isobenzofuranyl, benzo[b]thiophenyl, benzo[c]thiophenyl, indolyl, isoindolyl, benzo[d]isoxazolyl, benzo[c]isoxazolyl, benzo[d]oxazolyl, benzo[d]isothiazolyl, benzo[c]isothiazolyl, benzo[d]thiazolyl, indazolyl, benzo[d]imidazolyl, benzo[d]imidazolyl, and benzo[d][1,2,3]triazolyl.

In certain embodiments, the 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, is selected from the group consisting of: furanyl, thienyl, pyrrolyl, thiazolyl, oxazolyl, isothiazolyl, isoxazolyl, imidazolyl, pyrazolyl, 1H-1,2,3-triazolyl, 2H-1,2,3-triazolyl, 1,2,4-triazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, 1,3,5-triazinyl, 1,2,4-triazinyl, 1,2,3-triazinyl, 1,2,4-oxadiazolyl, 1,3,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,2,4-thiadiazolyl, 1,3,4-thiadiazolyl and 1,2,5-thiadiazolyl; and

the 8-12 membered bicyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, is selected from the group consisting of: benzofuranyl, isobenzofuranyl, benzo[b]thiophenyl, benzo[c]thiophenyl, indolyl, isoindolyl, benzo[d]isoxazolyl, benzo[c]isoxazolyl, benzo[d]oxazolyl, benzo[d]isothiazolyl, benzo[c]isothiazolyl, benzo[d]thiazolyl, indazolyl, benzo[d]imidazolyl, benzo[d]imidazolyl, and benzo[d][1,2,3]triazolyl.

In certain embodiments, the compound of Formula I is a compound of Formula II or III:

or a pharmaceutically acceptable salt thereof.

In certain embodiments, the compound of Formula I is a compound of Formula II:

or a pharmaceutically acceptable salt thereof.

In certain embodiments, the compound of Formula I is a compound of Formula III:

or a pharmaceutically acceptable salt thereof.

In certain embodiments, the compound of Formula I is a compound of Formula IV or V:

or a pharmaceutically acceptable salt thereof.

In certain embodiments, the compound of Formula I is a compound of Formula IV:

or a pharmaceutically acceptable salt thereof.

In certain embodiments, the compound of Formula I is a compound of Formula V:

or a pharmaceutically acceptable salt thereof.

In certain embodiments, w is 2.

In certain embodiments, R¹ is a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, optionally substituted with one, two, or three substituents independently selected from the group consisting of halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl.

In certain embodiments, R¹ is a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, optionally substituted with one, two, or three substituents independently selected from the group consisting of halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl;

wherein the 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, is selected from the group consisting of: furanyl, thienyl, pyrrolyl, thiazolyl, oxazolyl, isothiazolyl, isoxazolyl, imidazolyl, pyrazolyl, 1H-1,2,3-triazolyl, 2H-1,2,3-triazolyl, 1,2,4-triazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, 1,3,5-triazinyl, 1,2,4-triazinyl, 1,2,3-triazinyl, 1,2,4-oxadiazolyl, 1,3,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,2,4-thiadiazolyl, 1,3,4-thiadiazolyl and 1,2,5-thiadiazolyl.

In certain embodiments, R¹ is a 8-12 membered bicyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, optionally substituted with one, two, or three substituents independently selected from the group consisting of halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl.

In certain embodiments, R¹ is a 8-12 membered bicyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, optionally substituted with one, two, or three substituents independently selected from the group consisting of halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl;

wherein the 8-12 membered bicyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, is selected from the group consisting of: benzofuranyl, isobenzofuranyl, benzo[b]thiophenyl, benzo[c]thiophenyl, indolyl, isoindolyl, benzo[d]isoxazolyl, benzo[c]isoxazolyl, benzo[d]oxazolyl, benzo[d]isothiazolyl, benzo[c]isothiazolyl, benzo[d]thiazolyl, indazolyl, benzo[d]imidazolyl, benzo[d]imidazolyl, and benzo[d][1,2,3]triazolyl.

In certain embodiments, R¹ is phenyl optionally substituted with one, two, or three substituents independently selected from the group consisting of halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl.

In certain embodiments, R¹ is

wherein R¹¹, R¹² and R¹³ are independently selected from the group consisting of halo, cyano, C_1-6alkyl and C_1-6haloalkyl.

In certain embodiments, R¹ is

wherein R¹¹, R¹² and R¹³ are independently selected from the group consisting of F, Cl, and Br.

In certain embodiments R¹ is

In certain embodiments, R¹ is pyridyl, optionally substituted with one, two, or three substituents independently selected from the group consisting of halo, cyano, C_1-6alkyl and C_1-6haloalkyl.

In certain embodiments, R² is hydrogen or C_1-6alkyl.

In certain embodiments, R² is hydrogen or methyl.

In certain embodiments, R² is hydrogen.

In certain embodiments, R³ is a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6 alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl phenyl, and a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, wherein the phenyl or 5-6 membered monocyclic heteroaryl is optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl.

In certain embodiments, R³ is a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl phenyl, and a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, wherein the phenyl or 5-6 membered monocyclic heteroaryl is optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl;

wherein the 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, is selected from the group consisting of: furanyl, thienyl, pyrrolyl, thiazolyl, oxazolyl, isothiazolyl, isoxazolyl, imidazolyl, pyrazolyl, 1H-1,2,3-triazolyl, 2H-1,2,3-triazolyl, 1,2,4-triazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, 1,3,5-triazinyl, 1,2,4-triazinyl, 1,2,3-triazinyl, 1,2,4-oxadiazolyl, 1,3,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,2,4-thiadiazolyl, 1,3,4-thiadiazolyl and 1,2,5-thiadiazolyl.

In certain embodiments, R³ is a 8-12 membered bicyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, hydroxyC_1-6alkyl, R^aR^b—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl phenyl, and a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, wherein the phenyl or 5-6 membered monocyclic heteroaryl is optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl.

In certain embodiments, R³ is a 8-12 membered bicyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, hydroxyC_1-6alkyl, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl phenyl, and a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, wherein the phenyl or 5-6 membered monocyclic heteroaryl is optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl;

wherein the 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, is selected from the group consisting of: furanyl, thienyl, pyrrolyl, thiazolyl, oxazolyl, isothiazolyl, isoxazolyl, imidazolyl, pyrazolyl, 1H-1,2,3-triazolyl, 2H-1,2,3-triazolyl, 1,2,4-triazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, 1,3,5-triazinyl, 1,2,4-triazinyl, 1,2,3-triazinyl, 1,2,4-oxadiazolyl, 1,3,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,2,4-thiadiazolyl, 1,3,4-thiadiazolyl and 1,2,5-thiadiazolyl; and

the 8-12 membered bicyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, is selected from the group consisting of: benzofuranyl, isobenzofuranyl, benzo[b]thiophenyl, benzo[c]thiophenyl, indolyl, isoindolyl, benzo[d]isoxazolyl, benzo[c]isoxazolyl, benzo[d]oxazolyl, benzo[d]isothiazolyl, benzo[c]isothiazolyl, benzo[d]thiazolyl, indazolyl, benzo[d]imidazolyl, benzo[d]imidazolyl, and benzo[d][1,2,3]triazolyl.

In certain embodiments, R³ is phenyl optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl, phenyl, and a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, wherein the phenyl or 5-6 membered monocyclic heteroaryl is optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl.

In certain embodiments, R³ is phenyl optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl, phenyl, and a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, wherein the phenyl or 5-6 membered monocyclic heteroaryl is optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl;

wherein the 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, is selected from the group consisting of: furanyl, thienyl, pyrrolyl, thiazolyl, oxazolyl, isothiazolyl, isoxazolyl, imidazolyl, pyrazolyl, 1H-1,2,3-triazolyl, 2H-1,2,3-triazolyl, 1,2,4-triazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, 1,3,5-triazinyl, 1,2,4-triazinyl, 1,2,3-triazinyl, 1,2,4-oxadiazolyl, 1,3,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,2,4-thiadiazolyl, 1,3,4-thiadiazolyl and 1,2,5-thiadiazolyl.

In certain embodiments, R³ C_3-6cycloalkyl optionally substituted with one, two or three substituents independently selected from the group consisting of halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl, phenyl, and a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, wherein the phenyl or 5-6 membered monocyclic heteroaryl is optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl.

In certain embodiments, R³ C_3-6cycloalkyl optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6-alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl, phenyl, and a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, wherein the phenyl or 5-6 membered monocyclic heteroaryl is optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)OH, and —C(O)O—C_1-6alkyl;

wherein the 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, is selected from the group consisting of: furanyl, thienyl, pyrrolyl, thiazolyl, oxazolyl, isothiazolyl, isoxazolyl, imidazolyl, pyrazolyl, 1H-1,2,3-triazolyl, 2H-1,2,3-triazolyl, 1,2,4-triazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, 1,3,5-triazinyl, 1,2,4-triazinyl, 1,2,3-triazinyl, 1,2,4-oxadiazolyl, 1,3,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,2,4-thiadiazolyl, 1,3,4-thiadiazolyl and 1,2,5-thiadiazolyl.

In certain embodiments, R³ C_1-6alkyl optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl, phenyl, and a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, wherein the phenyl or 5-6 membered monocyclic heteroaryl is optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl.

In certain embodiments, R³ C_1-6alkyl optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl, phenyl, and a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, wherein the phenyl or 5-6 membered monocyclic heteroaryl is optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b,

C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl;

wherein the 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, is selected from the group consisting of: furanyl, thienyl, pyrrolyl, thiazolyl, oxazolyl, isothiazolyl, isoxazolyl, imidazolyl, pyrazolyl, 1H-1,2,3-triazolyl, 2H-1,2,3-triazolyl, 1,2,4-triazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, 1,3,5-triazinyl, 1,2,4-triazinyl, 1,2,3-triazinyl, 1,2,4-oxadiazolyl, 1,3,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,2,4-thiadiazolyl, 1,3,4-thiadiazolyl and 1,2,5-thiadiazolyl.

In certain embodiments, R³ is selected from the group consisting of:

wherein:

R³³ is independently selected for each occurrence from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl, phenyl, and a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, wherein the phenyl or 5-6 membered monocyclic heteroaryl is optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl;

R³⁴ is independently selected from the group consisting of hydrogen and C_1-4alkyl;

r is 0, 1 or 2; and

r2 is 0, 1, 2 or 3;

with the provisos that:

• • when R³ is thiophen-2-yl or furan-2-yl, r2 is 1, 2 or 3;
  • when R³ is pyrazol-4-yl, in at least one instance, R³³ is other than C_1-6alkyl; and
  • when R³ is phenyl, at least one of R³⁵, R³⁶ and R³⁷ is other than halo and C_1-6alkoxy.

In certain embodiments, R³ is selected from the group consisting of:

wherein:

R³³ is independently selected for each occurrence from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl, phenyl, and a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, wherein the phenyl or 5-6 membered monocyclic heteroaryl is optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)OH, and —C(O)O—C_1-6alkyl;

R³⁴ is independently selected from the group consisting of hydrogen and C_1-4alkyl;

r is 0, 1 or 2;

r2 is 0, 1, 2 or 3; and

the 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, is selected from the group consisting of: furanyl, thienyl, pyrrolyl, thiazolyl, oxazolyl, isothiazolyl, isoxazolyl, imidazolyl, pyrazolyl, 1H-1,2,3-triazolyl, 2H-1,2,3-triazolyl, 1,2,4-triazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, 1,3,5-triazinyl, 1,2,4-triazinyl, 1,2,3-triazinyl, 1,2,4-oxadiazolyl, 1,3,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,2,4-thiadiazolyl, 1,3,4-thiadiazolyl and 1,2,5-thiadiazolyl;

with the provisos that:

• • when R³ is thiophen-2-yl or furan-2-yl, r2 is 1, 2 or 3;
  • when R³ is pyrazol-4-yl, in at least one instance, R³³ is other than C_1-6alkyl; and
  • when R³ is phenyl, at least one of R³⁵, R³⁶ and R³⁷ is other than halo and C_1-6alkoxy.

In certain embodiments, R³ is selected from the group consisting of:

wherein:

R³³ is independently selected for each occurrence from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl, phenyl, and a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, wherein the phenyl or 5-6 membered monocyclic heteroaryl is optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl;

R³⁴ is independently selected from the group consisting of hydrogen and C_1-4alkyl;

r is 0, 1 or 2; and

r2 is 0, 1, 2 or 3;

with the provisos that:

• • when R³ is thiophen-2-yl or furan-2-yl, r2 is 1, 2 or 3;
  • when R³ is pyrazol-4-yl, in at least one instance, R³³ is other than C_1-6alkyl; and
  • when R³ is phenyl, at least one of R³⁵, R³⁶ and R³⁷ is other than halo and C_1-6alkoxy.

In certain embodiments, R³ is selected from the group consisting of:

wherein:

R³³ is independently selected for each occurrence from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl, phenyl, and a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, wherein the phenyl or 5-6 membered monocyclic heteroaryl is optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —NR^aR^b, —NR^c—S(O)_tC_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl;

R³⁴ is independently selected from the group consisting of hydrogen and C_1-4alkyl;

r is 0, 1 or 2;

r2 is 0, 1, 2 or 3; and

the 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms each selected from O, N, and S, is selected from the group consisting of: furanyl, thienyl, pyrrolyl, thiazolyl, oxazolyl, isothiazolyl, isoxazolyl, imidazolyl, pyrazolyl, 1H-1,2,3-triazolyl, 1,2,4-triazolyl, pyridinyl, pyridazinyl, pyrimidinyl pyrazinyl, 1,2,4-triazinyl, 1,2,4-oxadiazolyl, 1,3,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,2,4-thiadiazolyl, 1,3,4-thiadiazolyl and 1,2,5-thiadiazolyl;

with the provisos that:

• • when R³ is thiophen-2-yl or furan-2-yl, r2 is 1, 2 or 3;
  • when R³ is pyrazol-4-yl, in at least one instance, R³³ is other than C_1-6alkyl; and
    when R³ is phenyl, at least one of R³⁵, R³⁶ and R³⁷ is other than halo and C_1-6alkoxy.

In certain embodiments, R³ is

In certain embodiments, R³ is

wherein:

R³⁵, R³⁶ and R³⁷ are independently selected from the group consisting of: hydrogen, halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6 alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl, phenyl, and a 5-6 membered monocyclic heteroaryl having one, two, or three heteroatoms selected from the group consisting of O, N, and S, wherein the phenyl or 5-6 membered monocyclic heteroaryl is optionally substituted with one, two or three substituents independently selected from the group consisting of: halo, —OH, —CN, —NO₂, oxo, hydrazino, formyl, azido, silyl, siloxy, —S(O)_q—C_1-6alkyl, —NR^aR^b, —NR^c—S(O)_t—C_1-6alkyl, —S(O)_t—NR^aR^b, C_1-6alkyl, C_2-6alkenyl, C_2-6alkynyl, C_3-6cycloalkyl, haloC_1-6alkyl, hydroxyC_1-6alkyl, R^aR^bN—C_1-6alkyl-, C_1-6alkoxy, haloC_1-6alkoxy, hydroxyC_1-6alkoxy-, R^aR^bN—C_1-6alkoxy-, C_1-6alkoxyC_1-6alkyl, —C(O)NR^aR^b, —C(O)—C_1-6alkyl, —C(O)OH, and —C(O)O—C_1-6alkyl.

In certain embodiments, R³ is

wherein:

R³⁵, R³⁶ and R³⁷ are independently selected from the group consisting of hydrogen, hydroxy, cyano, carboxy, carbamoyl, haloC_1-4alkyl, haloC_1-4alkoxy, carboxyC_1-4alkoxy, R^aR^bN—C_1-4alkoxy, C_1-4alkoxycarbonyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl, and imidazolyl optionally substituted with C_1-4alkyl.

In certain embodiments, R³ is

In certain embodiments, R³ is

wherein:

R³³ is independently selected for each occurrence from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is

In certain embodiments, R³ is

wherein:

R³³ is independently selected for each occurrence from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is

In certain embodiments, R³ is

wherein:

R³³ is independently selected for each occurrence from the group consisting of:

halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is

In certain embodiments, R³ is

wherein:

R³³ is independently selected for each occurrence from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is

In certain embodiments, R³ is

wherein:

R³³ is selected from the group consisting of: hydrogen, halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is

In certain embodiments, R³ is

wherein:

R³³ is selected from the group consisting of: hydrogen, halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is

wherein:

R³³ is selected from the group consisting of: hydrogen, halo, C_1-4alkyl, haloC_1-4alkyl, thienyl, thiazolyl, pyrazolyl, 1-methylpyrazolyl, pyridinyl optionally substituted with halo, and phenyl optionally substituted with one or two substituents independently selected from the group consisting of halo and C_1-4alkoxy.

In certain embodiments, R³ is:

In certain embodiments, R³ is

wherein:

R³³ is selected from the group consisting of: hydrogen, halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is

In certain embodiments, R³ is:

wherein:

R³³ is selected from the group consisting of: hydrogen, halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is

In certain embodiments, R³ is

In certain embodiments, R³ is

wherein:

R³³ is selected from the group consisting of hydrogen, methyl and halide.

In certain embodiments, R³ is

In certain embodiments, R³ is:

wherein:

R³³ is independently selected for each occurrence from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl or hydroxyC_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkyl sulfonylamino.

In certain embodiments, R³ is

In certain embodiments, R³ is

wherein:

R³³ is selected from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl or hydroxyC_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is

wherein:

R³³ is selected from the group consisting of: halo, C_1-4alkyl, R^aR^bN—C_1-4alkoxy, thienyl, pyrimidinyl, pyrazolyl, 1-methylpyrazolyl, benzyl, pyridinyl optionally substituted with halo or haloC_1-4alkyl, and phenyl optionally substituted with one or two substituents independently selected from the group consisting of halo, cyano, C_1-4alkoxy, haloC_1-4alkyl and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is

In certain embodiments, R³ is

wherein:

R³³ is selected from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl or hydroxyC_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is

In certain embodiments, R³ is:

wherein:

R³³ is selected from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with

C_1-4alkyl or hydroxyC_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is

In certain embodiments, R³ is

wherein:

R³³ is independently selected for each occurrence from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, pyrazolyl optionally substituted with C_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is

wherein:

R³³ is selected from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, pyrazolyl optionally substituted with C_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is

In certain embodiments, R³ is

wherein:

R³³ is selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³ is

In certain embodiments, R³ is

wherein:

R³³ is selected from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³³ for each occurrence is selected from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, hydroxyC_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl, imidazolyl, phenyl, pyridyl, and pyrimidinyl, wherein the benzyl, thienyl, thiazolyl, pyrazolyl, imidazolyl, phenyl, pyridyl, and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, R³³ for each occurrence is selected from the group consisting of: halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, R^aR^bN—C_1-4alkoxy, benzyl, thienyl, thiazolyl, pyrazolyl optionally substituted with C_1-4alkyl or hydroxyC_1-4alkyl, imidazolyl optionally substituted with C_1-4alkyl, phenyl, pyridyl, and pyrimidinyl, wherein the phenyl, pyridyl and pyrimidinyl are optionally substituted with one or two substituents independently selected from the group consisting of halo, C_1-4alkyl, haloC_1-4alkyl, C_1-4alkoxy, and C_1-4alkylsulfonylamino.

In certain embodiments, in one occurrence R³³ is pyrazolyl or imidazolyl optionally substituted with C_1-4alkyl.

In certain embodiments, R⁴ is hydrogen, C_2-6alkenyl, C_2-6alkynyl or C_1-4alkyl optionally substituted with hydroxy, cyano, C_1-4alkoxy, haloC_1-4alkoxy, methylsulfonyl, diethylamino, carboxy, carbamoyl, benzyloxy, formyl, methoxyphenyl, pyrrolidinyl, morpholinyl, tetrahydrofuranyl or triazolyl.

In certain embodiments, R⁴ is hydrogen or C_1-6alkyl optionally substituted with a substituent selected from the group consisting of C_1-6alkoxy, —NR^aR^b, C_2-6alkenyl, —OH, —COOH, and C_1-6haloalkoxy.

In certain embodiments, R⁴ is C_1-6alkyl optionally substituted with a substituent selected from the group consisting of C_1-6alkoxy, —NR^aR^b, C_2-6alkenyl, —OH, —COOH, and C_1-6haloalkoxy.

In certain embodiments, R⁴ is —CH₂CH₂OCH₃.

In certain embodiments, R⁴ is methyl.

In certain embodiments, R⁵ is hydrogen, C_1-4alkyl, C_1-4alkoxy, or R^aR^bN—C_1-4alkyl.

In certain embodiments, R⁵ is hydrogen, methyl, methoxyethyl or dimethylaminoethyl.

In certain embodiments, R⁵ is hydrogen or methyl.

In certain embodiments, R⁵ is hydrogen.

In certain embodiments, R⁶ is hydrogen or C_1-6alkyl; In certain embodiments, R⁶ is hydrogen.

In certain embodiments, R² and R⁶ are hydrogen.

In certain embodiments, R² and R⁶ are hydrogen and w is 2.

In certain embodiments, R², R⁵ and R⁶ are hydrogen.

In certain embodiments, R², R⁵ and R⁶ are hydrogen and w is 2.

In certain embodiments, R², R⁵ and R⁶ are hydrogen and R⁴ is methyl.

In certain embodiments, R², R⁵ and R⁶ are hydrogen, R⁴ is methyl, and w is 2.

In certain embodiments, R¹ is 3-chloro-4-fluourophenyl and each of R² and R⁶ is hydrogen.

In certain embodiments, R¹ is 3-chloro-4-fluourophenyl, R² and R⁶ are hydrogen, and w is 2.

In certain embodiments, R¹ is 3-chloro-4-fluourophenyl and each of R², R⁵ and R⁶ is hydrogen.

In certain embodiments, R¹ is 3-chloro-4-fluourophenyl; each of R², R⁵ and R⁶ is hydrogen; and w is 2.

In certain embodiments, R¹ is 3-chloro-4-fluourophenyl; each of R², R⁵ and R⁶ is hydrogen; and R⁴ is methyl.

In certain embodiments, R¹ is 3-chloro-4-fluourophenyl; each of R², R⁵ and R⁶ is hydrogen, R⁴ is methyl, and w is 2.

It will be appreciated that all chemically allowable combinations of the embodiments described above, and elsewhere in this disclosure, are envisioned as further embodiments of the invention.

II. Pharmaceutical Compositions and Kits

In another aspect, the disclosure provides pharmaceutical compositions comprising a compound of Formula I, or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable excipient. In particular, the present disclosure provides pharmaceutical compositions comprising compounds as disclosed herein formulated together with one or more pharmaceutically acceptable carriers. These formulations include those suitable for oral, rectal, topical, buccal, parenteral (e.g., subcutaneous, intramuscular, intradermal, or intravenous), rectal, vaginal, or aerosol administration, although the most suitable form of administration in any given case will depend on the degree and severity of the condition being treated and on the nature of the particular compound being used. For example, disclosed compositions may be formulated as a unit dose, and/or may be formulated for oral or subcutaneous administration.

In another aspect, the disclosure provides a pharmaceutical composition comprises a compound of Table 2, or a pharmaceutically acceptable salt and/or stereoisomer thereof.

Exemplary pharmaceutical compositions of this disclosure may be used in the form of a pharmaceutical preparation, for example, in solid, semisolid or liquid form, which contains one or more of the compound of the disclosure, as an active ingredient, in admixture with an organic or inorganic carrier or excipient suitable for external, enteral or parenteral applications. The active ingredient may be compounded, for example, with the usual non-toxic, pharmaceutically acceptable carriers for tablets, pellets, capsules, suppositories, solutions, emulsions, suspensions, and any other form suitable for use. The active object compound is included in the pharmaceutical composition in an amount sufficient to produce the desired effect upon the process or condition of the disease.

For preparing solid compositions such as tablets, the principal active ingredient may be mixed with a pharmaceutical carrier, e.g., conventional tableting ingredients such as corn starch, lactose, sucrose, sorbitol, talc, stearic acid, magnesium stearate, dicalcium phosphate or gums, and other pharmaceutical diluents, e.g., water, to form a solid preformulation composition containing a homogeneous mixture of a compound of the disclosure, or a non-toxic pharmaceutically acceptable salt thereof. When referring to these preformulation compositions as homogeneous, it is meant that the active ingredient is dispersed evenly throughout the composition so that the composition may be readily subdivided into equally effective unit dosage forms such as tablets, pills and capsules.

In solid dosage forms for oral administration (capsules, tablets, pills, dragees, powders, granules and the like), the subject composition is mixed with one or more pharmaceutically acceptable carriers, such as sodium citrate or dicalcium phosphate, and/or any of the following: (1) fillers or extenders, such as starches, lactose, sucrose, glucose, mannitol, and/or silicic acid; (2) binders, such as, for example, carboxymethylcellulose, alginates, gelatin, polyvinyl pyrrolidone, sucrose and/or acacia; (3) humectants, such as glycerol; (4) disintegrating agents, such as agar-agar, calcium carbonate, potato or tapioca starch, alginic acid, certain silicates, and sodium carbonate; (5) solution retarding agents, such as paraffin; (6) absorption accelerators, such as quaternary ammonium compounds; (7) wetting agents, such as, for example, acetyl alcohol and glycerol monostearate; (8) absorbents, such as kaolin and bentonite clay; (9) lubricants, such a talc, calcium stearate, magnesium stearate, solid polyethylene glycols, sodium lauryl sulfate, and mixtures thereof; and (10) coloring agents. In the case of capsules, tablets and pills, the compositions may also comprise buffering agents. Solid compositions of a similar type may also be employed as fillers in soft and hard-filled gelatin capsules using such excipients as lactose or milk sugars, as well as high molecular weight polyethylene glycols and the like.

A tablet may be made by compression or molding, optionally with one or more accessory ingredients. Compressed tablets may be prepared using binder (for example, gelatin or hydroxypropylmethyl cellulose), lubricant, inert diluent, preservative, disintegrant (for example, sodium starch glycolate or cross-linked sodium carboxymethyl cellulose), surface-active or dispersing agent. Molded tablets may be made by molding in a suitable machine a mixture of the subject composition moistened with an inert liquid diluent. Tablets, and other solid dosage forms, such as dragees, capsules, pills and granules, may optionally be scored or prepared with coatings and shells, such as enteric coatings and other coatings well known in the pharmaceutical-formulating art.

Compositions for inhalation or insufflation include solutions and suspensions in pharmaceutically acceptable, aqueous or organic solvents, or mixtures thereof, and powders. Liquid dosage forms for oral administration include pharmaceutically acceptable emulsions, microemulsions, solutions, suspensions, syrups and elixirs. In addition to the subject composition, the liquid dosage forms may contain inert diluents commonly used in the art, such as, for example, water or other solvents, solubilizing agents and emulsifiers, such as ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethyl acetate, benzyl alcohol, benzyl benzoate, propylene glycol, 1,3-butylene glycol, oils (in particular, cottonseed, groundnut, corn, germ, olive, castor and sesame oils), glycerol, tetrahydrofuryl alcohol, polyethylene glycols and fatty acid esters of sorbitan, cyclodextrins and mixtures thereof.

Suspensions, in addition to the subject composition, may contain suspending agents as, for example, ethoxylated isostearyl alcohols, polyoxyethylene sorbitol and sorbitan esters, microcrystalline cellulose, aluminum metahydroxide, bentonite, agar-agar and tragacanth, and mixtures thereof.

Formulations for rectal or vaginal administration may be presented as a suppository, which may be prepared by mixing a subject composition with one or more suitable non-irritating excipients or carriers comprising, for example, cocoa butter, polyethylene glycol, a suppository wax or a salicylate, and which is solid at room temperature, but liquid at body temperature and, therefore, will melt in the body cavity and release the active agent.

Dosage forms for transdermal administration of a subject composition include powders, sprays, ointments, pastes, creams, lotions, gels, solutions, patches and inhalants. The active component may be mixed under sterile conditions with a pharmaceutically acceptable carrier, and with any preservatives, buffers, or propellants which may be required.

The ointments, pastes, creams and gels may contain, in addition to a subject composition, excipients, such as animal and vegetable fats, oils, waxes, paraffins, starch, tragacanth, cellulose derivatives, polyethylene glycols, silicones, bentonites, silicic acid, talc and zinc oxide, or mixtures thereof.

Powders and sprays may contain, in addition to a subject composition, excipients such as lactose, talc, silicic acid, aluminum hydroxide, calcium silicates and polyamide powder, or mixtures of these substances. Sprays may additionally contain customary propellants, such as chlorofluorohydrocarbons and volatile unsubstituted hydrocarbons, such as butane and propane.

Compositions and compounds of the present disclosure may alternatively be administered by aerosol. This is accomplished by preparing an aqueous aerosol, liposomal preparation or solid particles containing the compound. A non-aqueous (e.g., fluorocarbon propellant) suspension could be used. Sonic nebulizers may be used because they minimize exposing the agent to shear, which may result in degradation of the compounds contained in the subject compositions. Ordinarily, an aqueous aerosol is made by formulating an aqueous solution or suspension of a subject composition together with conventional pharmaceutically acceptable carriers and stabilizers. The carriers and stabilizers vary with the requirements of the particular subject composition, but typically include non-ionic surfactants (Tweens, Pluronics, or polyethylene glycol), innocuous proteins like serum albumin, sorbitan esters, oleic acid, lecithin, amino acids such as glycine, buffers, salts, sugars or sugar alcohols. Aerosols generally are prepared from isotonic solutions.

Pharmaceutical compositions of this disclosure suitable for parenteral administration comprise a subject composition in combination with one or more pharmaceutically-acceptable sterile isotonic aqueous or non-aqueous solutions, dispersions, suspensions or emulsions, or sterile powders which may be reconstituted into sterile injectable solutions or dispersions just prior to use, which may contain antioxidants, buffers, bacteriostats, solutes which render the formulation isotonic with the blood of the intended recipient or suspending or thickening agents.

Examples of suitable aqueous and non-aqueous carriers which may be employed in the pharmaceutical compositions of the disclosure include water, ethanol, polyols (such as glycerol, propylene glycol, polyethylene glycol, and the like), and suitable mixtures thereof, vegetable oils, such as olive oil, and injectable organic esters, such as ethyl oleate and cyclodextrins. Proper fluidity may be maintained, for example, by the use of coating materials, such as lecithin, by the maintenance of the required particle size in the case of dispersions, and by the use of surfactants

In another aspect, the disclosure provides enteral pharmaceutical formulations including a disclosed compound and an enteric material; and a pharmaceutically acceptable carrier or excipient thereof. Enteric materials refer to polymers that are substantially insoluble in the acidic environment of the stomach, and that are predominantly soluble in intestinal fluids at specific pHs. The small intestine is the part of the gastrointestinal tract (gut) between the stomach and the large intestine, and includes the duodenum, jejunum, and ileum. The pH of the duodenum is about 5.5, the pH of the jejunum is about 6.5 and the pH of the distal ileum is about 7.5. Accordingly, enteric materials are not soluble, for example, until a pH of about 5.0, of about 5.2, of about 5.4, of about 5.6, of about 5.8, of about 6.0, of about 6.2, of about 6.4, of about 6.6, of about 6.8, of about 7.0, of about 7.2, of about 7.4, of about 7.6, of about 7.8, of about 8.0, of about 8.2, of about 8.4, of about 8.6, of about 8.8, of about 9.0, of about 9.2, of about 9.4, of about 9.6, of about 9.8, or of about 10.0. Exemplary enteric materials include cellulose acetate phthalate (CAP), hydroxypropyl methylcellulose phthalate (HPMCP), polyvinyl acetate phthalate (PVAP), hydroxypropyl methylcellulose acetate succinate (HPMCAS), cellulose acetate trimellitate, hydroxypropyl methylcellulose succinate, cellulose acetate succinate, cellulose acetate hexahydrophthalate, cellulose propionate phthalate, cellulose acetate maleate, cellulose acetate butyrate, cellulose acetate propionate, copolymer of methylmethacrylic acid and methyl methacrylate, copolymer of methyl acrylate, methylmethacrylate and methacrylic acid, copolymer of methylvinyl ether and maleic anhydride (Gantrez ES series), ethyl methyacrylate-methylmethacrylate-chlorotrimethylammonium ethyl acrylate copolymer, natural resins such as zein, shellac and copal collophorium, and several commercially available enteric dispersion systems (e. g., Eudragit L30D55, Eudragit FS30D, Eudragit L100, Eudragit S100, Kollicoat EMM30D, Estacryl 30D, Coateric, and Aquateric). The solubility of each of the above materials is either known or is readily determinable in vitro. The foregoing is a list of possible materials, but one of skill in the art with the benefit of the disclosure would recognize that it is not comprehensive and that there are other enteric materials that would meet the objectives of the present disclosure.

Advantageously, the disclosure also provides kits for use by a e.g. a consumer in need of HBV infection treatment. Such kits include a suitable dosage form such as those described above and instructions describing the method of using such dosage form to mediate, reduce or prevent HBV infection. The instructions would direct the consumer or medical personnel to administer the dosage form according to administration modes known to those skilled in the art. Such kits could advantageously be packaged and sold in single or multiple kit units. An example of such a kit is a so-called blister pack. Blister packs are well known in the packaging industry and are being widely used for the packaging of pharmaceutical unit dosage forms (tablets, capsules, and the like). Blister packs generally consist of a sheet of relatively stiff material covered with a foil of a preferably transparent plastic material. During the packaging process recesses are formed in the plastic foil. The recesses have the size and shape of the tablets or capsules to be packed. Next, the tablets or capsules are placed in the recesses and the sheet of relatively stiff material is sealed against the plastic foil at the face of the foil which is opposite from the direction in which the recesses were formed. As a result, the tablets or capsules are sealed in the recesses between the plastic foil and the sheet. Preferably the strength of the sheet is such that the tablets or capsules can be removed from the blister pack by manually applying pressure on the recesses whereby an opening is formed in the sheet at the place of the recess. The tablet or capsule can then be removed via said opening.

It may be desirable to provide a memory aid on the kit, e.g., in the form of numbers next to the tablets or capsules whereby the numbers correspond with the days of the regimen which the tablets or capsules so specified should be ingested. Another example of such a memory aid is a calendar printed on the card, e.g., as follows “First Week, Monday, Tuesday, . . . etc. . . . Second Week, Monday, Tuesday, . . . ” etc. Other variations of memory aids will be readily apparent. A “daily dose” can be a single tablet or capsule or several pills or capsules to be taken on a given day. Also, a daily dose of a first compound can consist of one tablet or capsule while a daily dose of the second compound can consist of several tablets or capsules and vice versa. The memory aid should reflect this.

III. Methods

In a further aspect, a method for treating a hepatitis B infection in a patient in need thereof is provided, comprising administering to a subject or patient an effective amount of a disclosed compound, and/or administering a first disclosed compound and optionally, an additional, different disclosed compound(s). In another embodiment, a method for treating a hepatitis B infection in a patient in need thereof is provided, comprising administering to a subject or patient a therapeutically effective amount of a disclosed pharmaceutical composition or a pharmaceutical composition comprising a disclosed compound, or two or more disclosed compounds, and a pharmaceutically acceptable excipient.

For use in accordance with this aspect, the appropriate dosage is expected to vary depending on, for example, the particular compound employed, the mode of administration, and the nature and severity of the infection to be treated as well as the specific infection to be treated and is within the purview of the treating physician. Usually, an indicated administration dose may be in the range between about 0.1 to about 1000 μg/kg body weight. In some cases, the administration dose of the compound may be less than 400 μg/kg body weight. In other cases, the administration dose may be less than 200 μg/kg body weight. In yet other cases, the administration dose may be in the range between about 0.1 to about 100 μg/kg body weight. The dose may be conveniently administered once daily, or in divided doses up to, for example, four times a day or in sustained release form.

A compound of the present disclosure may be administered by any conventional route, in particular: enterally, topically, orally, nasally, e.g. in the form of tablets or capsules, via suppositories, or parenterally, e.g. in the form of injectable solutions or suspensions, for intravenous, intra-muscular, sub-cutaneous, or intra-peritoneal injection. Suitable formulations and pharmaceutical compositions will include those formulated in a conventional manner using one or more physiologically acceptable carriers or excipients, and any of those known and commercially available and currently employed in the clinical setting. Thus, the compounds may be formulated for oral, buccal, topical, parenteral, rectal or transdermal administration or in a form suitable for administration by inhalation or insufflation (either orally or nasally).

For oral administration, pharmaceutical compositions may take the form of, for example, tablets or capsules prepared by conventional means with pharmaceutically acceptable excipients such as binding agents (e.g. pregelatinised maize starch, polyvinylpyrrolidone or hydroxypropyl methylcellulose); fillers (e.g. lactose, microcrystalline cellulose or calcium hydrogen phosphate); lubricants (e.g. magnesium stearate, talc or silica); disintegrants (e.g. potato starch or sodium starch glycollate); or wetting agents (e.g. sodium lauryl sulphate). Tablets may be coated by methods well known in the art. Liquid preparations for oral administration may take the form of, for example, solutions, syrups or suspensions, or they may be presented as a dry product for constitution with water or other suitable vehicle before use. Such liquid preparations may be prepared by conventional means with pharmaceutically acceptable additives such as suspending agents (e.g. sorbitol syrup, cellulose derivatives or hydrogenated edible fats); emulsifying agents (e.g. lecithin or acacia); non-aqueous vehicles (e.g. almond oil, oily esters, ethyl alcohol or fractionated vegetable oils); and preservatives (e.g. methyl or propyl-p-hydroxybenzoates or sorbic acid). Preparations may also contain buffer salts, flavoring, coloring and sweetening agents as appropriate.

Preparations for oral administration may also be suitably formulated to give controlled-release or sustained release of the active compound(s) over an extended period. For buccal administration the compositions may take the form of tablets or lozenges formulated in a conventional manner known to the skilled artisan.

A disclosed compound may also be formulated for parenteral administration by injection e.g. by bolus injection or continuous infusion. Formulations for injection may be presented in unit dosage form e.g. in ampoules or in multi-dose containers, with an added preservative. The compositions may take such forms as suspensions, solutions or emulsions in oily or aqueous vehicles, and may contain additives such as suspending, stabilizing and/or dispersing agents. Alternatively, the compound may be in powder form for constitution with a suitable vehicle, e.g. sterile pyrogen-free water, before use. Compounds may also be formulated for rectal administration as suppositories or retention enemas, e.g. containing conventional suppository bases such as cocoa butter or other glycerides.

Also contemplated herein are methods and compositions that include a second active agent, or administering a second active agent. For example, in addition to being infected with HBV, a subject or patient can further have HBV infection-related co-morbidities, i.e., diseases and other adverse health conditions associated with, exacerbated by, or precipitated by being infected with HBV. Contemplated herein are disclosed compounds in combination with at least one other agent that has previously been shown to treat these HBV-infection-related conditions.

In some cases, a disclosed compound may be administered as part of a combination therapy in conjunction with one or more antivirals. Example antivirals include nucleoside analogs, interferon α, and other assembly effectors, for instance heteroaryldihydropyrimidines (HAPs) such as methyl 4-(2-chloro-4-fluorophenyl)-6-methyl-2-(pyridin-2-yl)-1,4-dihydropyrimidine-5-carboxylate (HAP-1). For example, provided herein is a method of treating a patient suffering from hepatitis B infection comprising administering to the patient a first amount of a disclosed compound and a second amount of an antiviral, or other anti HBV agent, for example a second amount of a second compound selected from the group consisting of: a HBV capsid assembly promoter (for example, GLS4, BAY 41-4109, AT-130, DVR-23 (e.g., as depicted below),

NVR 3-778, NVR1221 (by code); and N890 (as depicted below):

other CpAMs such as those disclosed in the following patent applications hereby incorporated by reference: WO2014037480, WO2014184328, WO2013006394, WO2014089296, WO2014106019, WO2013102655, WO2014184350, WO2014184365, WO2014161888, WO2014131847, WO2014033176, WO2014033167, and WO2014033170; Nucleoside analogs interfering with viral polymerase, such as entecavir (Baraclude), Lamivudine, (Epivir-HBV), Telbivudine (Tyzeka, Sebivo), Adefovir dipivoxil (Hepsera), Tenofovir (Viread), Tenofovir alafenamide fumarate (TAF), prodrugs of tenofavir (e.g. AGX-1009), L-FMAU (Clevudine), LB80380 (Besifovir) and:

viral entry inhibitors such as Myrcludex B and related lipopeptide derivatives; HBsAg secretion inhibitors such as REP 9AC′ and related nucleic acid-based amphipathic polymers, HBF-0529 (PBHBV-001), PBHBV-2-15 as depicted below:

and BM601 as depicted below:

disruptors of nucleocapsid formation or integrity such as NZ-4/W28F:

cccDNA formation inhibitors such as BSBI-25, CCC-0346, CCC-0975 (as depicted below):

HBc directed transbodies such as those described in Wang Y, et al, Transbody against hepatitis B virus core protein inhibits hepatitis B virus replication in vitro, Int. Immunopharmacol (2014), located at //dx.doi.org/10.1016/j.intimp.2015.01.028; antiviral core protein mutant (such as Cp183-V124W and related mutations as described in WO/2013/010069, WO2014/074906, each incorporated by reference); inhibitors of HBx-interactions such as RNAi, antisense and nucleic acid based polymers targeting HBV RNA; e.g., RNAi (for example ALN-HBV, ARC-520, TKM-HBV, ddRNAi), antisense (ISIS-HBV), or nucleic acid based polymer: (REP 2139-Ca); immunostimulants such as Interferon alpha 2a (Roferon), Intron A (interferon alpha 2b), Pegasys (peginterferon alpha 2a), Pegylated IFN 2b, IFN lambda 1a and PEG IFN lambda 1a, Wellferon, Roferon, Infergen, lymphotoxin beta agonists such as CBE11 and BS1); Non-Interferon Immune enhancers such as Thymosin alpha-1 (Zadaxin) and Interleukin-7 (CYT107); TLR-7/9 agonists such as GS-9620, CYT003, Resiquimod; Cyclophilin Inhibitors such as NVP018; OCB-030; SCY-635; Alisporivir; NIM811 and related cyclosporine analogs; vaccines such as GS-4774, TG1050, Core antigen vaccine; SMAC mimetics such as birinapant and other IAP-antagonists; Epigenetic modulators such as KMT inhibitors (EZH1/2, G9a, SETD7, Suv39 inhibitors), PRMT inhibitors, HDAC inhibitors, SIRT agonists, HAT inhibitors, WD antagonists (e.g. OICR-9429), PARP inhibitors, APE inhibitors, DNMT inhibitors, LSD1 inhibitors, JMJD HDM inhibitors, and Bromodomain antagonists; kinase inhibitors such as TKB1 antagonists, PLK1 inhibitors, SRPK inhibitors, CDK2 inhibitors, ATM & ATR kinase inhibitors; STING Agonists; Ribavirin; N-acetyl cysteine; NOV-205 (BAM205); Nitazoxanide (Alinia), Tizoxanide; SB 9200 Small Molecule Nucleic Acid Hybrid (SMNH); DV-601; Arbidol; FXR agonists (such as GW 4064 and Fexaramin); antibodies, therapeutic proteins, gene therapy, and biologics directed against viral components or interacting host proteins.

In some embodiments, the disclosure provides a method of treating a hepatitis B infection in a patient in need thereof, comprising administering a first compound selected from any one of the disclosed compounds, and one or more other HBV agents each selected from the group consisting of HBV capsid assembly promoters, HBF viral polymerase interfering nucleosides, viral entry inhibitors, HBsAg secretion inhibitors, disruptors of nucleocapsid formation, cccDNA formation inhibitors, antiviral core protein mutant, HBc directed transbodies, RNAi targeting HBV RNA, immunostimulants, TLR-7/9 agonists, cyclophilin inhibitors, HBV vaccines, SMAC mimetics, epigenetic modulators, kinase inhibitors, and STING agonists. In some embodiments, the disclosure provides a method of treating a hepatitis B infection in a patient in need thereof, comprising administering an amount of a disclosed compound, and administering another HBV capsid assembly promoter.

In some embodiments, the first and second amounts together comprise a pharmaceutically effective amount. The first amount, the second amount, or both may be the same, more, or less than effective amounts of each compound administered as monotherapies. Therapeutically effective amounts of a disclosed compound and antiviral may be co-administered to the subject, i.e., administered to the subject simultaneously or separately, in any given order and by the same or different routes of administration. In some instances, it may be advantageous to initiate administration of a disclosed compound first, for example one or more days or weeks prior to initiation of administration of the antiviral. Moreover, additional drugs may be given in conjunction with the above combination therapy.

In another embodiment, a disclosed compound may be conjugated (e.g., covalently bound directly or through molecular linker to a free carbon, nitrogen (e.g. an amino group), or oxygen (e.g. an active ester) of a disclosed compound), with a detection moiety, for e.g., a fluorophore moiety (such a moiety may for example re-emit a certain light frequency upon binding to a virus and/or upon photon excitation). Contemplated fluorophores include AlexaFluor® 488 (Invitrogen) and BODIPY FL (Invitrogen), as well as fluorescein, rhodamine, cyanine, indocarbocyanine, anthraquinones, fluorescent proteins, aminocoumarin, methoxycoumarin, hydroxycoumarin, Cy2, Cy3, and the like. Such disclosed compounds conjugated to a detection moiety may be used in e.g. a method for detecting HBV or biological pathways of HBV infection, e.g., in vitro or in vivo; and/or methods of assessing new compounds for biological activity.

EXAMPLES

The compounds described herein can be prepared in a number of ways based on the teachings contained herein and synthetic procedures known in the art. In the description of the synthetic methods described below, it is to be understood that all proposed reaction conditions, including choice of solvent, reaction atmosphere, reaction temperature, duration of the experiment and workup procedures, can be chosen to be the conditions standard for that reaction, unless otherwise indicated. It is understood by one skilled in the art of organic synthesis that the functionality present on various portions of the molecule should be compatible with the reagents and reactions proposed. Substituents not compatible with the reaction conditions will be apparent to one skilled in the art, and alternate methods are therefore indicated. The starting materials for the examples are either commercially available or are readily prepared by standard methods from known materials.

At least some of the compounds identified as “intermediates” herein are contemplated as compounds of the disclosure.

Abbreviations:

• • DCM Dichloromethane
  • EtOAC Ethyl acetate
  • MeOH Methanol
  • DMSO Dimethyl sulfoxide
  • NMO N-Methylmorpholine N-oxide
  • LiHMDS Lithium bis(trimethylsilyl)amide
  • p-TSA p-Toluenesulfonic acid
  • DMF N,N-Dimethylformamide
  • THF Tetrahydrofuran
  • TLC Thin-layer chromatography
  • LCMS Liquid chromatography-mass spectrometry
  • HPLC High performance liquid chromatography

General Procedure for the Synthesis of 2, 4-Diketoester:

To a stirred solution of corresponding acetyl compound (1 eq.) in dry THF (10V) at −78° C. under Ar atmosphere, LiHMDS (1M in THF, 1.3 eq.) was added and stirred at the same temperature for 1 h. To this solution, dimethyl oxalate (1.5 eq.) in dry THF (5V) was added drop wise at −78° C. and the resulting reaction mixture was stirred at room temperature for overnight. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was concentrated under reduced pressure. The residue was diluted with water; the precipitated solid was collected by filtration, washed with ethyl acetate followed by diethyl ether and dried under reduced pressure to afford desired compound (Note: The desired compound was isolated in enol form and used as such for the next step).

General Procedure for the Synthesis of Cyclic Sulphonamide:

Method A (HCl (g)/MeOH, Sealed Tube):

To a stirred solution of 2, 4-diketoester (1 eq.) and sulfamide (1 eq.) in MeOH (10V), in sealed tube, HCl gas (generated by sodium chloride+H₂SO₄) was purged for 2 h at 0° C. The resulting reaction mixture was stirred at 80° C. for 24 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was cooled to 0° C., precipitated solid was filtered, washed with water followed by cold methanol and dried in vacuo to afford cyclic sulphonamide.

Method B (4N HCl in MeOH, RB Flask):

In a round bottom flask fitted with reflux condenser, 2, 4-diketoester (1 eq.) and sulfamide (1 eq.) was taken in 4 N methanolic HCl (10V). The resulting reaction mixture was stirred at 60° C. for 16 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was cooled to 0° C., precipitated solid was filtered, washed with water followed by diethyl ether and dried in vacuo to afford cyclic sulphonamide.

General Procedure for Alkylation

Method A (Alkylation Using NaH/MeI):

To a stirred solution of cyclic sulphonamide (1 eq.) in dry DMF (8V) at 0° C. under Ar atmosphere, NaH (60% w/w in mineral oil, 1.5 eq.) was added and stirred at 0° C. for 45 min. To this solution, MeI (1.1 eq.) was added slowly and resulting reaction mixture was stirred at room temperature for 12 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was diluted with ice cold water; the obtained solid was collected by filtration. The solid was washed with diethyl ether and dried in vacuo to afford N-alkylated desired compound after silica gel column chromatography.

Method B (Alkylation Using Mitsunobu Reaction):

To a stirred solution of cyclic sulphonamide (1 eq.) in dry THF (4V) at 0° C. under Ar atmosphere, TPP (2 eq.) and methanol (10 eq.) was added and stirred at 0° C. for 45 min. To this solution, DEAD/DIAD (2 eq.) was added slowly and resulting reaction mixture (color change to dark brown) was heated at 60° C. for 16 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture concentrated under vacuum, residue obtained was taken in diethyl ether, stirred for 30 min. and filtered. The solid obtained was further stirred in methanol for 30 min., filtered and dried in vacuo to afford N-alkylated desired compound (Note: a few compounds were further purified using silica gel column chromatography).

General Procedure for Amidation:

Method a (AlMe₃ Mediated Amidation):

To a stirred solution of corresponding anilines (3 eq.) in DCM/Toluene at 0° C. under Ar atmosphere, AlMe₃ (2M in toluene, 3 eq.) was added and the reaction mixture was stirred at 0° C. for 10 min and continued stirring at room temperature for 1 h. To this solution, corresponding ester compound (1 eq.) was added at 0° C. under Ar atmosphere and resulting reaction mixture was refluxed at 40° C. for overnight. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was cooled to 0° C.; quenched with 1N HCl solution slowly and extracted with DCM. The combined organic layers were collected, dried over anhydrous sodium sulphate and concentrated in vacuo. The crude compound was purified by silica gel column chromatography followed by trituration with diethyl ether to afford the compound HBV-CSU_Int. (Note: The reaction was heated at 110° C. for a few compounds wherein toluene was used as solvent).

Method B (Hydrolysis Followed by Acid-Amine Coupling Using HATU):

To a solution of corresponding ester compound (1 eq.) in 10V of CH₃CN:H₂O (1:1) at 0° C. was added TEA (5 eq.) and the resulting reaction mixture was stirred at the same temperature till clear solution was observed (usually 4-6 h). The progress of reaction was monitored by TLC. After completion, the reaction mixture was concentrated under reduced pressure, and the residue obtained was acidified with 6N HCl and extracted with ethyl acetate. The combined organic layer was dried over anhydrous sodium sulphate, filtered and concentrated under reduced pressure to afford acid derivative which was used in the next step after trituration with di-ethyl ether. To a stirred solution of above acid compound (1 eq.) in DCM/DMF (10V) at 0° C. was added DIPEA (2 eq.), stirred for 15 min, followed by addition of HATU (2 eq.), again stirred for 15 min and then corresponding aniline (1.2 eq.) was added. The reaction mixture was then stirred at room temperature for overnight. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was diluted with ice cold water and extracted with DCM. The combined organic layers were dried over anhydrous sodium sulphate and concentrated under reduced pressure to afford a crude compound. The crude compound was taken in methanol (10V), stirred for 15 min., filtered and dried under reduced pressure to afford compound desired compound.

Method C (Hydrolysis Followed by Acid-Amine Coupling Using EDCI.HCl):

To a solution of corresponding ester compound (1 eq.) in 10V of CH₃CN: H₂O (1:1) at 0° C. was added TEA (5 eq.) and the resulting reaction mixture was stirred at the same temperature till clear solution was observed (usually 4-6 h). The progress of reaction was monitored by TLC. After completion, the reaction mixture was concentrated under reduced pressure, and residue obtained was acidified with 6N HCl and extracted with ethyl acetate. The combined organic layer was dried over sodium sulphate, filtered and concentrated under reduced pressure to afford acid derivative which was used in the next step after trituration with di-ethyl ether. To a stirred solution of above acid compound (1 eq.) in DMF (10-25V) at 0° C. was added EDCI.HCl (1.5 eq.) and HOBt (1.5 eq.) with stirring for 15 min; followed by addition of DIPEA (3 eq.) then the corresponding aniline (1.2 eq.). The reaction mixture was then stirred at room temperature for overnight. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was diluted with ice cold water and extracted with DCM. The combined organic layers were dried over anhydrous sodium sulphate and concentrated under reduced pressure to afford a crude compound. The crude compound was purified using silica gel column chromatography to afford compound HBV-CSU_Int.

General Procedure for Reduction:

To a stirred solution of compound HBV-CSU_Int (1 eq.) in EtOH at 0° C. under Ar atmosphere, NaBH₄ (2 eq.) was added and stirred at room temperature for 20 min. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was concentrated in vacuo, the residue obtained was diluted with water and extracted using ethyl acetate. The combined organic layers were collected, dried over anhydrous sodium sulphate, filtered, concentrated in vacuo and purified by silica gel column chromatography to afford the desired compound. Note: The regioselective alkylation and the cis stereochemistry were confirmed by NOE experiments for a few representative compounds.

General Method for Suzuki Coupling:

To a mixture of bromo compound (1 eq.), boronic acid/boronate ester (1 eq.) in 1, 4-dioxane, 2M solution of potassium phosphate was added, purged with Ar atmosphere for 15 min, followed by the addition of tetrakistriphenyl phosphine palladium (0.06 eq.), and stirred at 90° C. for overnight. The progress of the reaction was monitored by TLC. After completion of the reaction, the reaction mixture was filtered through Celite and evaporated to dryness. The residue was taken in ethyl acetate, washed with water, followed by brine, dried over anhydrous sodium sulfate and evaporated under reduced pressure. The crude product was purified by column chromatography/preparative HPLC to afford the desired product.

General Method for Stille Coupling:

To a mixture of bromo compound (1 eq.) in toluene/dioxane, stannane reagent (1 eq.) was added and purged with Ar atmosphere for 15 min followed by the addition of tetrakistriphenyl phosphine palladium (0.06 eq.). The resulting reaction mixture was then stirred at 90° C. for overnight. The progress of the reaction was monitored by TLC. After completion of the reaction, the reaction mixture was filtered through Celite and evaporated to dryness. The residue was taken in ethyl acetate, washed with water, brine, dried over anhydrous sodium sulfate and evaporated under reduced pressure. The crude product was purified by column chromatography/preparative HPLC to afford the desired product. (Note: The reaction has been performed in acetonitrile solvent for some compounds wherein solubility of bromo compound is an issue).

General Method for Negishi Coupling:

To an Ar purged mixture of bromo compound (1 eq.) in 1, 4-dioxane was added PdCl₂(dppf). DCM (0.1 eq.) and reaction mixture was stirred for 10 min; then Me₂Zn (2 eq.) was added and stirred at 90° C. for 6 h. The progress of the reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with methanol followed by water and then extracted using ethyl acetate. The combined organic layer was washed with brine, dried over anhydrous sodium sulfate and evaporated under reduced pressure to afford the crude product which was purified by column chromatography/preparative HPLC to afford the desired product as a solid.

Methods for Chiral Separation:

Method A

Column: YMC chiral Amylose-SA, 250 mm×20 mm, 5 micron

Mobile Phase:

A: n-Hexane+0.1% DEA

B: DCM: MeOH (1:1)

Isocratic: 30-90% B

Flow rate: 18 mL/Min

Method B

Column: DIACEL CHIRALPACK-IA, 250 mm×20 mm, 5 micron

Mobile Phase:

A: n-Hexane+0.1% DEA

B: DCM: MeOH (1:1)

Gradient: Hold 50% B till 4 min then 100% B at 5 min & hold up to 15 min
Flow rate: 18 mL/Min

Method C

Column: CHIRALPACK-IA, 250 mm×30 mm, 5 micron

Mobile Phase:

A: n-Hexane+0.1% DEA

B: DCM: MeOH (1:1)

Isocratic: 30-90% B

Flow rate: 30 mL/Min

The Chiral Purity was Confirmed by Using Following Methods:

Method A

Column: YMC chiral Amylose-SA, 250 mm×4.6 mm, 5 micron

Mobile Phase:

A: n-Hexane+0.1% DEA

B: DCM: MeOH (1:1)

Isocratic: 30-90% B

Flow rate: 1 mL/Min

Method B

Column: YMC chiral art cellulose-SC, 250 mm×4.6 mm, 5 micron

Mobile Phase:

A: n-Hexane+0.1% DEA

B: DCM: MeOH (1:1)

Isocratic: 30-90% B

Flow rate: 1 mL/Min

Method C

Column: CHIRALPACK-IA, 250 mm×4.6 mm, 5 micron

Mobile Phase:

A: n-Hexane+0.1% DEA

B: DCM: MeOH (1:1)

Isocratic: 30-90% B

Flow rate: 30 mL/Min
The first eluting compound was labelled as HBV-CSU-XXX-ISO-I and second eluting compound was labelled as HBV-CSU-XXX-ISO-II.
Note: The mobile phases have been changed based on solubility and other issues encountered during prep-HPLC purification as well as analysis. In few cases additives like TFA and MeSO₃H were used. For few samples instead of Isocratic gradient eluation method was adopted.

Scheme 1:

General Synthetic Scheme for 5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide Derivatives with N-alkyl & Aniline Variations

Target	R variation	Aniline (R1/R2/R3 variation)
HBV-CSU-006	Methyl
HBV-CSU-007	Methyl
HBV-CSU-010	Methyl
HBV-CSU-011	Methyl
HBV-CSU-012	Methyl
HBV-CSU-013	Methyl
HBV-CSU-014	Methyl
HBV-CSU-015	Methyl
HBV-CSU-016	Methyl
HBV-CSU-017	Methyl
HBV-CSU-018	Methyl
HBV-CSU-019	Methyl
HBV-CSU-020	Methyl
HBV-CSU-024	Ethyl
HBV-CSU-036	Methyl
HBV-CSU-040	Allyl
HBV-CSU-045	Methyl
HBV-CSU-046	Methyl
HBV-CSU-047	Methyl
HBV-CSU-048	Methyl
HBV-CSU-049	Methyl
HBV-CSU-023_Int-1	Methyl

Synthesis of Methyl 2, 4-dioxo-4-(thiophen-2-yl)butanoate (3)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 26 g (77%, reaction scale is 20 g) as a yellow colored solid. TLC: 10% MeOH/DCM (R_f: 0.1); ¹H NMR (DMSO-d₆, 400 MHz): δ 7.68 (d, J=5.2 Hz, 1H), 7.61 (d, J=4.4 Hz, 1H), 7.10 (t, J=5.2 Hz, 1H), 6.34 (s, 1H), 3.69 (s, 3H); LCMS Calculated for C₉H₈O₄S: 212.01; Observed: 212.95 (M+1)⁺.

Synthesis of Methyl 5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (4)

Title compound was synthesized using general method for the synthesis of cyclic sulfonamide described above to afford 8 g (62%, reaction scale is 10 g) as yellow colored solid. TLC: 20% MeOH/DCM (R_f: 0.1); ¹H NMR (DMSO-d₆, 400 MHz): δ 11.50 (br.s, 1H), 8.06 (d, J=4.0 Hz, 1H), 7.93 (d, J=5.2 Hz, 1H), 7.23 (t, J=4.0 Hz, 1H), 6.99 (s, 1H), 3.87 (s, 3H); LCMS Calculated for C₉H₈N₂O₄S₂: 271.99; LCMS observed: 272.85 (M+1)⁺.

Synthesis of Methyl 2-methyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (5)

Title compound was synthesized using general method A for alkylation described above to afford 4 g (77%, reaction scale is 5 g) as yellow colored solid. TLC: 40% EtOAc/hexanes (R_f: 0.4); ¹H NMR (DMSO-d₆, 400 MHz): δ 8.23 (d, J=4.0 Hz, 1H), 8.10 (d, J=4.8 Hz, 1H), 7.32-7.30 (m, 2H), 3.94 (s, 3H), 3.50 (s, 3H); LCMS Calculated for C₁₀H₁₀N₂O₄S₂: 286.01; LCMS observed: 286.94 (M+1)⁺.

Methyl 2-ethyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (5)

Title compound was synthesized using general method A for alkylation described above to afford 0.2 g (crude) as a light yellow solid. TLC: 40% EtOAc/hexanes (R_f: 0.4); ¹H NMR (DMSO-d₆, 400 MHz): δ 7.93 (d, J=4.0 Hz, 1H), 7.83 (d, J=4.8 Hz, 1H), 7.21-7.19 (m, 1H), 6.81 (s, 1H), 4.32-4.25 (m, 2H), 1.32 (t, J=6.8 Hz, 3H), 3H merged in solvent peak; LCMS Calculated for C₁₁H₁₂N₂O₄S₂: 300.02; LCMS observed: 300.90 (M+1)⁺.

Methyl 2-allyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (5)

Title compound was synthesized using general method A for alkylation described above to afford 0.13 g (45%, reaction scale is 0.25 g)) as a yellow solid. TLC: 50% EtOAc/hexanes (R_f: 0.3); ¹H NMR (DMSO-d₆, 400 MHz) δ 8.26 (dd, J=3.9, 1.3 Hz, 1H), 8.16-8.06 (m, 1H), 7.41 (d, J=1.2 Hz, 1H), 7.34-7.31 (m, 1H), 5.97-5.90 (m, 1H), 5.34-5.18 (m, 2H), 4.59-4.50 (m, 2H), 3.92 (s, 3H); LCMS Calculated for C₁₂H₁₂N₂O₄S₂: 312.02; LCMS observed: 312.95 (M+1)⁺.

2-Methyl-N-phenyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-006_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

N-(4-fluorophenyl)-2-methyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-007_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

N-(3-chlorophenyl)-2-methyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-010_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

N-(3,4-difluorophenyl)-2-methyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-011_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

2-Methyl-5-(thiophen-2-yl)-N-(3-(trifluoromethyl)phenyl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-012_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

2-Methyl-5-(thiophen-2-yl)-N-(m-tolyl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-013_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

N-(4-chlorophenyl)-2-methyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-014_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

N-(3-chloro-4-fluorophenyl)-N,2-dimethyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-015_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

N-(3-bromo-4-fluorophenyl)-2-methyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-016_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

N-(3-bromophenyl)-2-methyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-017_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

N-(4-chloro-3-fluorophenyl)-2-methyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-018_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

N-(4-Cyanophenyl)-2-methyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-019_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

N-(3-Cyanophenyl)-2-methyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-020_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-023_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

N-(3-chloro-4-fluorophenyl)-2-ethyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-024_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

2-Methyl-5-(thiophen-2-yl)-N-(3,4,5-trifluorophenyl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-036_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

2-Allyl-N-(3-chloro-4-fluorophenyl)-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-040_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

N-(3-Cyano-4-fluorophenyl)-2-methyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-045_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

N-(4-Fluoro-3-(trifluoromethyl)phenyl)-2-methyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-046_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

N-(3, 5-Dichlorophenyl)-2-methyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-047_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

N-(3,5-Dibromophenyl)-2-methyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-048_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

N-(3-Bromo-4,5-difluorophenyl)-2-methyl-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-049_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 5 and corresponding amine (see Table 1 for analytical data).

Cis-2-Methyl-N-phenyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-006)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-006_Int (see Table 2 for analytical data).

Cis-N-(4-Fluorophenyl)-2-methyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-007)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-007_Int (see Table 2 for analytical data).

Cis-N-(3-chlorophenyl)-2-methyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-010 & HBV-CSU-010-ISO-I)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-010_Int (see Table 2 for analytical data).

Cis-N-(3,4-difluorophenyl)-2-methyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-011)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-011_Int (see Table 2 for analytical data).

Cis-2-Methyl-5-(thiophen-2-yl)-N-(3-(trifluoromethyl)phenyl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-012)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-012_Int (see Table 2 for analytical data).

Cis-2-Methyl-5-(thiophen-2-yl)-N-(m-tolyl)-1,2,6-thiadiazinane-3-carboxamide dioxide (HBV-CSU-013)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-013_Int (see Table 2 for analytical data).

Cis-N-(4-chlorophenyl)-2-methyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-014)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-014_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-N-2-dimethyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-015)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-015_Int (see Table 2 for analytical data).

Cis-N-(3-Bromo-4-fluorophenyl)-2-methyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-016 & HBV-CSU-016-ISO-I)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-016_Int (see Table 2 for analytical data).

Cis-N-(3-Bromophenyl)-2-methyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-017 & HBV-CSU-017-ISO-I)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-017_Int (see Table 2 for analytical data).

Cis-N-(4-Chloro-3-fluorophenyl)-2-methyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-018)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-018_Int (see Table 2 for analytical data).

Cis-N-(4-cyanophenyl)-2-methyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-019)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-019_Int (see Table 2 for analytical data).

Cis-N-(3-cyanophenyl)-2-methyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-020 & HBV-CSU-020-ISO-I)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-020_Int (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-ethyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-024)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-24_Int (see Table 2 for analytical data).

Cis-2-Methyl-5-(thiophen-2-yl)-N-(3,4,5-trifluorophenyl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-036)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-36_Int (see Table 2 for analytical data).

Cis-2-Allyl-N-(3-chloro-4-fluorophenyl)-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-040)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-40_Int (see Table 2 for analytical data).

Cis-N-(3-cyano-4-fluorophenyl)-2-methyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-045 & HBV-CSU-045-ISO-I)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-45_Int (see Table 2 for analytical data).

Cis-N-(4-Fluoro-3-(trifluoromethyl)phenyl)-2-methyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-046-ISO-I)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-46_Int (see Table 2 for analytical data).

Cis-N-(3,5-Dichlorophenyl)-2-methyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-047-ISO-I)

The above titled compound had been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-47_Int (see Table 2 for analytical data).

Cis-N-(3,5-Dibromophenyl)-2-methyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-048-ISO-I)

The above titled compound had been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-48_Int (see Table 2 for analytical data).

Cis-N-(3-Bromo-4,5-difluorophenyl)-2-methyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-049-ISO-I)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-49_Int (see Table 2 for analytical data).

Scheme 2:

General Synthetic Scheme for 5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-Dioxide Derivatives with N-alkyl Variations at C-6

Cis-N-(3-Chloro-4-fluorophenyl)-2,6-dimethyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-023)

To a stirred solution of compound HBV-CSU-023_Int 1 (0.15 g, 0.372 mmol) in acetonitrile (3 mL) at 0° C., K₂CO₃ (0.154 g, 1.16 mmol) was added and stirred at room temperature for 10 min. To this solution, MeI (0.063 g, 0.446 mmol) was added. The reaction mixture was stirred at room temperature for 12 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was diluted with water and extracted using ethyl acetate. The combined organic layers were washed with brine, dried over anhydrous sodium sulphate and concentrated in vacuo. The crude compound was purified by silica gel column chromatography to afford the desired compound (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-6-(2-(dimethylamino)ethyl)-2-methyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-043-ISO-I & ISO-II)

To a stirred solution of compound HBV-CSU-023_Int I (0.25 g, 0.621 mmol) in acetonitrile (10 mL), K₂CO₃ (0.257 g, 1.86 mmol) and 2-chloro-N,N-dimethylethan-1-amine hydrochloride (0.107 g, 0.745 mmol) were added and stirred at room temperature for 12 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was concentrated in vacuo and the crude compound obtained was purified by chiral preparative HPLC to afford the desired compound (25 mg, 8.41%) as a white solid. TLC: 40% EtOAc/hexanes (R_f: 0.1); (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-6-(2-methoxyethyl)-2-methyl-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-064)

To a stirred solution of compound HBV-CSU-023_Int 1 (0.05 g, 0.123 mmol.) in acetonitrile (3 mL) at 0° C., K₂CO₃ (0.051 g, 0.371 mmol) was added and stirred at room temperature for 10 min. To this solution, 1-bromo-2-methoxyethane (0.034 g, 0.247 mmol) was added. The reaction mixture was stirred at room temperature for 12 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was diluted with water and extracted with ethyl acetate. The combined organic layers were washed with brine, dried over anhydrous sodium sulphate and concentrated in vacuo. The crude compound was purified by silica gel column chromatography to afford the desired compound (see Table 2 for analytical data).

Scheme 3:

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-2-(2-methoxyethyl)-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-25, HBV-CSU-025-ISO-I &II) & Cis-N-(3-chloro-4-fluorophenyl)-6-(2-methoxyethyl)-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-044-ISO-I &II)

Methyl 2-(2-methoxyethyl)-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (7) and methyl 2-(2-methoxyethyl)-3-(thiophen-2-yl)-2H-1,2,6-thiadiazine-5-carboxylate 1,1-dioxide (7A)

To a stirred solution of compound 3 (5 g, 23.58 mmol) and compound 6 (3.6 g, 23.58 mmol) in MeOH (40 mL), in sealed tube, HCl gas (generated by sodium chloride+H₂SO₄) was purged for 2 h at 0° C. The resulting reaction mixture was stirred at 80° C. for 24 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was concentrated under reduced pressure. The crude compound was purified by silica gel column chromatography using 15% EtOAc/hexane to afford mixture of compounds 7 and 7A (1 g, 13%) as a white solid TLC: 40% EtOAc/hexanes (R_f: 0.6); LCMS Calculated for C₉H₈N₂O₄S₂: 330.03; LCMS observed: 330.95 (M+1)⁺.

N-(3-Chloro-4-fluorophenyl)-2-(2-methoxyethyl)-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-025_Int) and N-(3-chloro-4-fluorophenyl)-2-(2-methoxyethyl)-3-(thiophen-2-yl)-2H-1,2,6-thiadiazine-5-carboxamide 1,1-dioxide (HBV-CSU-044_Int)

The above titled compounds have been isolated as inseparable mixture of compounds by following the general procedure (Method A) described above for amidation by using corresponding 7/7A and corresponding amine. The desired product formation was confirmed by LCMS. LCMS Calculated for C₁₇H₁₅ClFN₃O₄S₂: 443.02; LCMS observed: 444.04 (M+1)⁺.

N-(2-methoxyethyl)sulfamide (6)

To a stirred solution of Sulfamide (1 g, 10.42 mmol) in THF (5 mL), 2-methoxyethan-1-amine (0.78 g, 10.41 mmol) was added and the reaction mixture was stirred at 100° C. in microwave for 30 min. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was concentrated in vacuo. The crude compound was purified by silica gel column chromatography to afford the compound 6 (6.05 g, 75.43%) as a colorless oil. TLC: 5% MeOH/DCM (R_f: 0.5); ¹H NMR (DMSO-d₆, 400 MHz): δ 6.48 (br. s, 3H), 3.40-3.32 (m, 2H), 3.23 (s, 3H), 3.02-2.99 (m, 2H).

Cis-N-(3-chloro-4-fluorophenyl)-2-(2-methoxyethyl)-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-025, HBV-CSU-025-ISO-I & HBV-CSU-025-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding inseparable mixture of HBV-CSU-025_Int/HBV-CSU-044_Int. The regio-isomers were separated using prep-HPLC and then subjected to chiral HPLC separation (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-6-(2-methoxyethyl)-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-044-ISO-I & HBV-CSU-044-ISO-II)

The above titled compound has been synthesized by following the general procedure described above for reduction by using inseparable mixture of HBV-CSU-025_Int/HBV-CSU-044_Int. The regio-isomers were separated using prep-HPLC and then subjected to chiral HPLC separation (see Table 2 for analytical data).

Scheme 4:

General Synthetic Scheme for 5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-Dioxide Derivatives with N-alkyl Variations at C-6

Target	R variation	Aniline (X = Br/Cl)	Step 3	Step 4
HBV-CSU-027	Methyl		Alkylation (Method A)	Amidation (Method A)
HBV-CSU-058			Alkylation (Method A)	Amidation (Method A)
HBV-CSU-059			Alkylation (Method A)	Amidation (Method A)
HBV-CSU-060	Methyl		Alkylation (Method A)	Amidation (Method A)
HBV-CSU-071			Mitsunobu (Method B)	Amidation (Method C)
HBV-CSU-072			Mitsunobu (Method B)	Amidation (Method B)
HBV-CSU-077			Mitsunobu (Method B)	Amidation (Method B)
HBV-CSU-079			Mitsunobu (Method B)	Amidation (Method A)
HBV-CSU-082			Mitsunobu (Method B)	Amidation (Method C)
HBV-CSU-083			Mitsunobu (Method B)	Amidation (Method B)
HBV-CSU-089			Mitsunobu (Method B)	Amidation (Method B)
HBV-CSU-090			Mitsunobu (Method B)	Amidation (Method A)
HBV-CSU-094			Mitsunobu (Method B)	Amidation (Method B)
HBV-CSU-095			Mitsunobu (Method B)	Amidation (Method B)
HBV-CSU-108	PMB		Mitsunobu (Method B)	Amidation (Method B)
HBV-CSU-109			Mitsunobu (Method B)	Amidation (Method C)
HBV-CSU-142			Mitsunobu (Method B)	Amidation (Method C)
HBV-CSU-143			Mitsunobu (Method B)	Amidation (Method C)

Methyl 2,4-dioxo-4-(thiazol-2-yl)butanoate (10)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 11 g (66%, reaction scale is 10 g) as a yellow colored solid. TLC: 5% MeOH/DCM (R_f: 0.2); ¹H NMR (DMSO-d₆, 400 MHz): δ 7.92-7.82 (m, 2H), 6.72 (s, 1H), 3.68 (s, 3H); LCMS Calculated for C₈H₇NO₄S: 213.01; Observed: 213.97 (M+1)⁺.

Methyl 5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (11)

Title compound was synthesized using general method for the synthesis of cyclic sulfonamide described above to afford 4 g (45%, reaction scale is 7 g) as a light yellow colored solid. TLC: 10% MeOH/DCM (R_f: 0.1); ¹H NMR (DMSO-d₆, 400 MHz,) δ 11.13 (br. s, 1H), 7.99 (d, J=3.2 Hz, 1H), 7.93 (d, J=3.2 Hz, 1H), 6.96 (s, 1H), 3.80 (s, 3H); LCMS observed for C₈H₇N₃O₄S₂: 273.85 (M+1)⁺.

Methyl 2-methyl-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (12)

Title compound was synthesized using general method A for alkylation described above to afford 1.3 g (80%, reaction scale is 1.5 g) as yellow colored solid. TLC: 50% EtOAc/hexanes (R_f: 0.4); ¹H-NMR (DMSO-d₆, 400 MHz): δ 8.25 (d, J=2.8 Hz, 1H), 8.19 (d, J=2.8 Hz, 1H), 7.43 (s, 1H), 3.91 (s, 3H), 3.56 (s, 3H); LCMS observed for C₉H₉N₃O₄S₂: 287.00, Observed: 287.90 (M+1)⁺.

Methyl 2-(2-methoxyethyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (12)

Title compound was synthesized using general method C for alkylation described above to afford 1.1 g (45.3%, reaction scale is 2 g). LCMS observed for C₁₁H₁₃N₃O₅S₂: 331.03, Observed: 332 (M+1)⁺.

Methyl 2-(2-(tert-butoxy)ethyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (12)

Title compound was synthesized using general method B for alkylation described above to afford 2.5 g (61%, reaction scale is 3 g). ¹H NMR (DMSO-d₆, 500 MHz) δ 8.30 (d, J=2.9 Hz, 1H), 8.25 (d, J=2.9 Hz, 1H), 7.49 (s, 1H), 4.29 (t, J=4.9 Hz, 2H), 3.92 (s, 3H), 3.38 (t, J=4.9 Hz, 2H), 0.94 (s, 9H).

Methyl 5-(thiazol-2-yl)-2-(2-(trifluoromethoxy)ethyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (12)

Title compound was synthesized using general method B for alkylation described above to afford 0.7 g (crude, reaction scale is 0.5 g). LCMS observed for C₁₁H₁₀F₃N₃O₅S₂: 385.00, Observed: 385.95 (M+1)⁺.

Methyl 2-allyl-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (12)

Title compound was synthesized using general method A for alkylation described above to afford 0.85 g (74.56%, reaction scale is 1 g/trans-esterified product also observed which was carried forward as mixture to next step); LCMS observed for C₁₁H₁₁N₃O₄S₂: 313.02, Observed: 313.6 (M+1)⁺.

Methyl 2-(prop-2-yn-1-yl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (12)

Title compound was synthesized using general method B for alkylation described above to afford 0.75 g (66.37%, reaction scale is 1 g); LCMS observed for C₁₁H₉N₃O₄S₂: 311.00, Observed: 311.95 (M+1)⁺.

Methyl 2-(3-methoxypropyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (12)

Title compound was synthesized using general method B for alkylation described above to afford 1.5 g (59.28%, reaction scale is 2 g); LCMS observed for C₁₂H₁₅N₃O₅S₂: 345.05, Observed: 346 (M+1)⁺.

Methyl 2-((tetrahydrofuran-2-yl)methyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (12)

Title compound was synthesized using general method B for alkylation described above to afford 0.4 g (61%, reaction scale is 0.5 g). ¹H NMR (500 MHz, DMSO-d₆): δ 8.31 (d, J=2.9 Hz, 1H), 8.25 (d, J=2.9 Hz, 1H), 7.48 (s, 1H), 4.32-4.27 (m, 1H), 4.24-4.14 (m, 1H), 3.99-3.93 (m, 1H), 3.93 (s, 3H), 3.61-3.54 (m, 1H), 3.47-3.41 (m, 1H), 1.96-1.85 (m, 1H), 1.78-1.58 (m, 2H), 1.51-1.42 (m, 1H).

Methyl 2-(2-morpholinoethyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (12)

Title compound was synthesized using general method B for alkylation described above to afford 150 mg (crude, reaction scale is 1.5 g). LCMS observed for C₁₄H₁₈N₄O₅S₂: 386.07, Observed: 387.20 (M+1)⁺.

Methyl 2-(3-methoxy-3-methylbutyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (12)

Title compound was synthesized using general method B for alkylation described above to afford 1.5 g (55%, reaction scale is 1.73 g). ¹H NMR (400 MHz, DMSO-d₆): δ 8.30 (d, J=3.0 Hz, 1H), 8.24 (d, J=3.0 Hz, 1H), 7.49 (s, 1H), 4.04-3.98 (m, 2H), 3.95 (s, 3H), 3.08 (s, 3H), 2.03-1.96 (m, 2H), 1.12 (s, 6H).

Methyl 2-(but-3-yn-1-yl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (12)

Title compound was synthesized using general method B for alkylation described above to afford 310 mg (26%, reaction scale is 1 g). ¹H-NMR (DMSO-d₆, 400 MHz): δ 8.32 (d, J=3.1 Hz, 1H), 8.25 (d, J=3.0 Hz, 1H), 7.56 (s, 1H), 4.21 (t, J=7.0 Hz, 2H), 3.96 (s, 3H), 3.00 (t, J=2.6 Hz, 1H), 2.65 (td, J=7.0, 2.6 Hz, 2H); LCMS observed for C₁₂H₁₁N₃O₄S₂: 325.02, Observed: 326.10 (M+1)⁺.

Methyl 2-(2-(benzyloxy)ethyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (12)

Title compound was synthesized using general method B for alkylation described above to afford 780 mg (17.7%, reaction scale is 2 g); LCMS observed for C₁₇H₁₇N₃O₅S₂: 407.06, Observed: 408.05 (M+1)⁺.

Methyl 2-(4-methoxybenzyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (12)

Title compound was synthesized using general method B for alkylation described above to afford 900 mg (24.32%, reaction scale is 2 g). ¹H-NMR (DMSO-d₆, 400 MHz): δ 8.32 (d, J=2.8 Hz, 1H), 8.24 (d, J=2.8 Hz, 1H), 7.49 (s, 1H), 7.19 (d, J=8.8 Hz, 1H), 6.91 (d, J=8.4 Hz, 1H), 5.16 (s, 2H), 3.85 (s, 3H), 3.72 (s, 3H).

Methyl 2-(2-(methylthio)ethyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (12)

Title compound was synthesized using general method B for alkylation described above to afford 1.5 g (60%, reaction scale is 2 g). ¹H-NMR (DMSO-d₆, 400 MHz): 8.31 (d, J=3.1 Hz, 1H), 8.25 (d, J=2.9 Hz, 1H), 7.55 (s, 1H), 4.23 (t, J=7.0 Hz, 2H), 3.96 (s, 3H), 2.83 (t, J=7.0 Hz, 2H), 2.04 (s, 3H); LCMS observed for C₁₁H₁₃N₃O₄S₃: 347.01, Observed: 347.10 (M+1)⁺.

Methyl 2-(2-ethoxyethyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (12)

Title compound was synthesized using general method B for alkylation described above to afford 1.3 g (52%, reaction scale is 2 g). ¹H-NMR (DMSO-d₆, 400 MHz): δ 8.31 (d, J=3.1 Hz, 1H), 8.25 (d, J=3.1 Hz, 1H), 7.47 (s, 1H), 4.29 (t, J=5.0 Hz, 2H), 3.93 (s, 3H), 3.49 (t, J=5.0 Hz, 2H), 3.30 (q, J=7.4 Hz, 2H), 0.97 (t, J=7.0 Hz, 3H); LCMS observed for C₁₂H₁₅N₃O₅S₂: 345.05, Observed: 346.10 (M+1)⁺.

Methyl 2-(2-isopropoxyethyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (12)

Title compound was synthesized using general method B for alkylation described above to afford 1.3 g (66%, reaction scale is 1.5 g). ¹H-NMR (DMSO-d₆, 400 MHz): δ 8.31 (d, J=3.0 Hz, 1H), 8.25 (d, J=3.1 Hz, 1H), 7.49 (s, 1H), 4.29 (t, J=5.0 Hz, 2H), 3.93 (s, 3H), 3.46 (t, J=5.0 Hz, 2H), 3.43-3.35 (m, 1H), 0.92 (d, J=6.0 Hz, 6H); LCMS observed for C₁₃H₁₇N₃O₅S₂: 359.06, Observed: 359.90 (M+1)⁺.

N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-027_Int)

The above titled compounds have been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 12 and corresponding amine. The desired product formation was confirmed by LCMS and the crude intermediate carried forward to the next step. LCMS observed for C₁₄H₁₀ClFN₄O₃S₂: 399.99, Observed: 400.90 (M+1)⁺.

N-(3-chloro-4-fluorophenyl)-2-(2-methoxyethyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-058_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 12 and corresponding amine (see Table 1 for analytical data).

N-(3-Bromo-4-fluorophenyl)-2-(2-methoxyethyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-059_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 12 and corresponding amine (see Table 1 for analytical data).

N-(3-Bromo-4-fluorophenyl)-2-methyl-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-060_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 12 and corresponding amine (see Table 1 for analytical data).

2-(tert-Butoxy)ethyl)-N-(3-chloro-4-fluorophenyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-071_Int)

The above titled compound has been synthesized by following the general procedure (Method C) described above for amidation by using corresponding 12 and corresponding amine see Table 1 for analytical data).

N-(3-Chloro-4-fluorophenyl)-5-(thiazol-2-yl)-2-(2-(trifluoromethoxy)ethyl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-072_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding 12 and corresponding amine (see Table 1 for analytical data).

N-(3-Chloro-4-fluorophenyl)-2-(3-methoxypropyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-077_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding 12 and corresponding amine (see Table 1 for analytical data).

N-(3-Chloro-4-fluorophenyl)-2-((tetrahydrofuran-2-yl)methyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-079_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 12 and corresponding amine (see Table 1 for analytical data).

N-(3-chloro-4-fluorophenyl)-2-(2-morpholinoethyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-082_Int)

The above titled compound has been synthesized by following the general procedure (Method C) described above for amidation by using corresponding 12 and corresponding amine (see Table 1 for analytical data).

N-(3-chloro-4-fluorophenyl)-2-(3-methoxy-3-methylbutyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-083_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding 12 and corresponding amine (see Table 1 for analytical data).

N-(3-Chloro-4-fluorophenyl)-2-(prop-2-yn-1-yl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-089_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding 12 and corresponding amine (see Table 1 for analytical data).

2-(But-3-yn-1-yl)-N-(3-chloro-4-fluorophenyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-090_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 12 and corresponding amine (see Table 1 for analytical data).

2-Allyl-N-(3-chloro-4-fluorophenyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-094_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 12 and corresponding amine (see Table 1 for analytical data).

2-(2-(Benzyloxy)ethyl)-N-(3-chloro-4-fluorophenyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-095_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding 12 and corresponding amine (see Table 1 for analytical data).

N-(3-Chloro-4-fluorophenyl)-2-(4-methoxybenzyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-108_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding 12 and corresponding amine (see Table 1 for analytical data).

N-(3-Chloro-4-fluorophenyl)-2-(2-(methylthio)ethyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-109_Int)

The above titled compound has been synthesized by following the general procedure (Method C) described above for amidation by using corresponding 12 and corresponding amine (see Table 1 for analytical data).

N-(3-chloro-4-fluorophenyl)-2-(2-ethoxyethyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-142_Int)

The above titled compound has been synthesized by following the general procedure (Method C) described above for amidation by using corresponding 12 and corresponding amine (see Table 1 for analytical data).

N-(3-chloro-4-fluorophenyl)-2-(2-isopropoxyethyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-143_Int)

The above titled compound has been synthesized by following the general procedure (Method C) described above for amidation by using corresponding 12 and corresponding amine (see Table 1 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-027, HBV-CSU-027-ISO-I & HBV-CSU-027-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-027_Int (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-(2-methoxyethyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-058, HBV-CSU-058-ISO-I & HBV-CSU-058-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-058_Int (see Table 2 for analytical data).

Cis-N-(3-bromo-4-fluorophenyl)-2-(2-methoxyethyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-059, HBV-CSU-059-ISO-I & HBV-CSU-059-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-059_Int (see Table 2 for analytical data).

Cis-N-(3-bromo-4-fluorophenyl)-2-methyl-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-060-ISO-I &HBV-CSU-060-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-060_Int. The chiral HPLC separation provided desired compound (see Table 2 for analytical data).

Cis-2-(2-(tert-Butoxy)ethyl)-N-(3-chloro-4-fluorophenyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-071, HBV-CSU-071-ISO-I & HBV-CSU-071-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-071_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(thiazol-2-yl)-2-(2-(trifluoromethoxy)ethyl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-072, HBV-CSU-072-ISO-I & HBV-CSU-072-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-072_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-(3-methoxypropyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-077-ISO-I & HBV-CSU-077-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-077_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-((tetrahydrofuran-2-yl)methyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-079-Rac-A & HBV-CSU-079-Rac-B)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-079_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-(2-morpholinoethyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-082)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-082_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-(3-methoxy-3-methylbutyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-083, HBV-CSU-083-ISO-I & HBV-CSU-083-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-083_Int (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-(prop-2-yn-1-yl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-089-ISO-I & HBV-CSU-089-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-089_Int (see Table 2 for analytical data).

Cis-2-(But-3-yn-1-yl)-N-(3-chloro-4-fluorophenyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-090, HBV-CSU-090-ISO-I, HBV-CSU-090-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-090_Int (see Table 2 for analytical data).

Cis-2-Allyl-N-(3-chloro-4-fluorophenyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-094-ISO-I & HBV-CSU-094-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-094_Int (see Table 2 for analytical data).

Cis-2-(2-(benzyloxy)ethyl)-N-(3-chloro-4-fluorophenyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-095, HBV-CSU-095-ISO-I & HBV-CSU-095-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-095_Int (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-(4-methoxybenzyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-108)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-108_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-(2-(methylthio)ethyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-109, HBV-CSU-109-ISO-I & HBV-CSU-109-ISO-II)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-109_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-(2-ethoxyethyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-142, HBV-CSU-142-ISO-I & HBV-CSU-142-ISO-II)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-142_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-(2-isopropoxyethyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-143)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-143_Int (see Table 2 for analytical data).

Scheme 5:

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-5-(5-fluorothiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-029-ISO-I)

2-(5-Bromothiophen-2-yl)-2-methyl-1,3-dioxolane (14)

To a stirred solution of compound 13 (5 g, 24.39 mmol) in toluene (50 mL), p-TSA (0.413 g, 2.43 mmol) and ethane-1,2-diol (6.04 g, 97.56 mmol) were added and the reaction was refluxed for 24 h using Dean Stark apparatus. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was diluted with water and extracted with ethyl acetate. The combined organic layers were washed with water and brine; dried over anhydrous sodium sulphate and concentrated in vacuo. The crude compound was purified by silica gel column chromatography to afford the title compound 14 (2.7 g, 44.33%) as a white solid. TLC: 40% EtOAc/hexanes (R_f: 0.6); ¹H NMR (CDCl₃, 400 MHz): δ 6.92 (d, J=3.2 Hz, 1H), 6.80 (d, J=4.0 Hz, 1H), 4.08-3.95 (m, 4H), 7.78 (s, 3H).

1-(5-Fluorothiophen-2-yl)ethan-1-one (15)

To a stirred solution of compound 14 (5 g, 20 mmol) in dry THF (50 mL) at −78° C. under Ar atmosphere, n-BuLi (2.5 M, 13.04 mL, 30 mmol) was added dropwise and stirred at same temperature for 45 min. To this solution, NFSI dissolved in dry THF (10 mL) (8.19 g, 26 mmol) was added at −78° C. slowly. The resulting reaction mixture was stirred at room temperature for 12 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was quenched with sat. NH₄Cl solution and extracted with diethyl ether. The combined organic layers were washed with water and brine; dried over anhydrous sodium sulphate and concentrated in vacuo. The crude compound was purified by silica gel column chromatography using 2% EtOAc/hexane to afford fluoro-substituted compound (2.7 g). To a stirred solution above, the fluoro-substituted compound (2.7 g, 14.36 mmol) in THF (20 mL), 3N HCl (10 mL) was added and stirred at room temperature for 3 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was diluted with water and extracted with ethyl acetate. The combined organic layers were washed with water and brine; dried over anhydrous sodium sulphate and concentrated in vacuo to afford the title compound 15 (2.2 g, crude) as a light brown oil. TLC: 10% EtOAc/hexane (R_f: 0.4); ¹H NMR (DMSO-d₆, 400 MHz): δ 7.40 (d, J=4.0 Hz, 1H), 6.55 (dd, J=4.0, 1.2 Hz, 1H), 2.51 (s, 3H).

Methyl 4-(5-fluorothiophen-2-yl)-2,4-dioxobutanoate (16)

To a stirred solution of Compound 15 (2.3 g, 15.97 mmol) in dry THF (20 mL) at −78° C. under Ar atmosphere, LiHMDS (1M in THF, 20.76 mL, 20.76 mmol) was added and stirred at the same temperature for 1 h. To this solution, Compound 2 (2.45 g, 20.76 mmol) in dry THF (10 mL) was added drop wise at −78° C. The resulting reaction mixture was stirred at room temperature for overnight. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was concentrated under reduced pressure. The residue was diluted with water; the precipitated solid was collected by filtration, washed with ethyl acetate followed by diethyl ether and dried under reduced pressure to afford compound 16 (2.7 g, 62.64%) as yellow solid. (Note: 16 was isolated in enol form and used as such for the next step). TLC: 10% MeOH in DCM (R_f: 0.1); LCMS Calculated for C₉H₇FO₄S: 230.0; Observed: 230.88 (M+1)⁺.

Methyl 5-(5-fluorothiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (17)

To a stirred solution of compound 16 (2.5 g, 10.86 mmol) and sulfamide (1.25 g, 10.86 mmol) in MeOH (30 mL), in sealed tube, HCl gas (generated by sodium chloride+H₂SO₄) was purged for 2 h at 0° C. The resulting reaction mixture was stirred at 80° C. for 24 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was cooled to 0° C. and filtered. The solid was washed with cold methanol and dried in vacuo to afford compound 17 (1.8 g, 57.14%) LCMS Calculated for C₉H₇FN₂O₄S₂: 289.98; LCMS observed: 290.94 (M+1)⁺.

Methyl 5-(5-fluorothiophen-2-yl)-2-methyl-2H-1, 2, 6-thiadiazine-3-carboxylate 1,1-dioxide (18)

To a stirred solution of compound 17 (1.2 g, 4.14 mmol.) in DMF (10 mL) at 0° C., K₂CO₃ (1.8 g, 12.41 mmol) was added and stirred at room temperature for 10 min. To this solution, MeI (1.22 g, 8.28 mmol) was added. The reaction mixture was stirred at room temperature for 12 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was diluted with water and extracted with ethyl acetate. The combined organic layers were washed with water and brine; dried over anhydrous sodium sulphate and concentrated in vacuo. The crude compound was purified by silica gel column chromatography to afford the compound 18 (0.4 g, 32%) as brown colored solid. TLC: 40% EtOAc/hexanes (R_f: 0.7); ¹H NMR (DMSO-d₆, 400 MHz): δ 8.13-8.11 (m, 1H), 7.33 (s, 1H), 7.05-7.04 (m, 1H), 3.94 (s, 3H), 3.49 (s, 3H); LCMS Calculated for C₁₀H₉FN₂O₄S₂: 304.00; LCMS observed: 304.85 (M+1)⁺.

N-(3-chloro-4-fluorophenyl)-5-(5-fluorothiophen-2-yl)-2-methyl-2H-1, 2, 6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-029_Int)

To a stirred solution of compound 18 (0.287 g, 1.97 mmol) in DCM (10 mL) at 0° C. under Ar atmosphere, AlMe₃ (2M in toluene, 0.986 mL, 1.97 mmol) was added and the reaction mixture was stirred at 0° C. for 10 min and continued stirring at room temperature for 1 h. To this solution, aniline (0.2 g, 0.657 mmol) was added at 0° C. under Ar atmosphere and resulting reaction mixture was refluxed at 40° C. for overnight. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was cooled to 0° C., quenched with 1N HCl solution slowly, and extracted with DCM. The combined organic layers were collected, dried over anhydrous sodium sulphate, and concentrated in vacuo. The crude compound was purified by silica gel column chromatography followed by trituration with diethyl ether to afford the compound HBV-CSU-029_Int. (see Table 1 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(5-fluorothiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-029-ISO-I)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-029_Int. The chiral HPLC separation provided desired compound (see Table 2 for analytical data).

Scheme 6:

General Synthetic Scheme for 5-(Phenyl/Pyridyl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide Derivatives with Substituted Phenyl/Pyridyl, N-2 Alkyl & Aniline Variations

Target	#28 (R variation)	N-Alkyl (R1 Variation)	Aniline (R2/R3 variation)
HBV-CSU-031		Methyl
HBV-CSU-032		Methyl
HBV-CSU-033		Methyl
HBV-CSU-112		Methyl
HBV-CSU-113		Methyl
HBV-CSU-200		Methyl
HBV-CSU-202		Methyl
HBV-CSU-204		Methyl
HBV-CSU-210
HBV-CSU-211		Methyl
HBV-CSU-212		Methyl
HBV-CSU-215		Methyl
HBV-CSU-217		Methyl
HBV-CSU-230		Methyl
HBV-CSU-231		Methyl
HBV-CSU-232		Methyl
HBV-CSU-259		Methyl
HBV-CSU-261		Methyl
HBV-CSU-262		Methyl
HBV-CSU-263		Methyl
HBV-CSU-264		Methyl
HBV-CSU-265		Methyl
HBV-CSU-283		Methyl

Synthesis of Methyl 2, 4-dioxo-4-(pyridin-2-yl)butanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 3.2 g (37.47%, reaction scale is 5 g); LCMS Calculated for C₁₀H₉NO₄: 207.05; Observed: 208.00 (M+1)⁺.

Synthesis of Methyl 4-(5-fluoropyridin-2-yl)-2,4-dioxobutanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 2.5 g (96.15%, reaction scale is 1.6 g); LCMS Calculated for C₁₀H₈FNO₄: 225.04; Observed: 225.90 (M+1)⁺.

Synthesis of Methyl 2,4-dioxo-4-(pyridin-3-yl)butanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 2 g (23.52%, reaction scale is 5 g); LCMS Calculated for C₁₀H₉NO₄: 207.05; Observed: 207.95 (M+1)⁺.

Synthesis of Methyl 4-(4-fluorophenyl)-2,4-dioxobutanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 13.84 g (85.0%, reaction scale is 10 g); LCMS Calculated for C₁₁H₉FO₄: 224.05; Observed: 225.00 (M+1)⁺.

Synthesis of Methyl 2,4-dioxo-4-phenylbutanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 17.24 g (66%, reaction scale is 15 g); LCMS Calculated for C₁₁H₁₀O₄: 206.06; Observed: 207.10 (M+1)⁺.

Synthesis of Methyl 4-(4-methoxyphenyl)-2,4-dioxobutanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 27 g (crude, reaction scale is 15 g); LCMS Calculated for C₁₂H₁₂O₅: 236.07; Observed: 237.00 (M+1)⁺.

Synthesis of Methyl 4-(4-bromophenyl)-2,4-dioxobutanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 33 g (92.18%, reaction scale is 25 g); LCMS Calculated for C₁₁H₉BrO₄: 283.97; Observed: 286.95 (M+2)⁺.

Synthesis of Methyl 4-(3-methoxyphenyl)-2,4-dioxobutanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 28.3 g (Crude, reaction scale is 25 g); LCMS Calculated for C₁₂H₁₂O₅: 236.07; Observed: 236.95 (M+1)⁺.

Synthesis of Methyl 4-(2-methoxyphenyl)-2,4-dioxobutanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 28 g (70.93%, reaction scale is 25 g); LCMS Calculated for C₁₂H₁₂O₅: 236.07; Observed: 237.00 (M+1)⁺.

Synthesis of Methyl 2,4-dioxo-4-(4-(trifluoromethyl)phenyl)butanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 34 g (93.32%, reaction scale is 25 g); LCMS Calculated for C₁₂H₉F₃O₄: 274.05; Observed: 275.05 (M+1)⁺.

Synthesis of Methyl 4-(3,4-difluorophenyl)-2,4-dioxobutanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 30 g (77.41%, reaction scale is 25 g); LCMS Calculated for C₁₁H₈F₂O₄: 242.04; Observed: 242.95 (M+1)⁺.

Synthesis of Methyl 4-(3-fluorophenyl)-2,4-dioxobutanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 30 g (73.65%, reaction scale is 25 g); LCMS Calculated for C₁₁H₉FO₄: 224.05; Observed: 225.00 (M+1)⁺.

Synthesis of Methyl 2,4-dioxo-4-(4-(trifluoromethoxy)phenyl)butanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 70 g (98.92%, reaction scale is 50 g); LCMS Calculated for C₁₂H₉F₃O₅: 290.04; Observed: 288.75 (M−1)⁻.

Synthesis of Methyl 2,4-dioxo-4-(3-(trifluoromethyl)phenyl)butanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 25 g (68.60%, reaction scale is 25 g).

Synthesis of Methyl 4-(3-chlorophenyl)-2,4-dioxobutanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 18 g (96%, reaction scale is 12 g); LCMS Calculated for C₁₁H₉ClO₄: 240.02; Observed: 240.90 (M+1)⁺.

Synthesis of Methyl 2,4-dioxo-4-(3-(trifluoromethoxy)phenyl)butanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 15 g (crude, reaction scale is 10 g); LCMS Calculated for C₁₂H₉F₃O₅: 290.04; Observed: 291.25 (M+1)⁺.

Synthesis of Methyl 4-(4-(difluoromethoxy)phenyl)-2,4-dioxobutanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 12 g (crude, reaction scale is 10 g); LCMS Calculated for C₁₂H₁₀F₂O₅: 272.05; Observed: 272.95 (M+1)⁺.

Synthesis of Methyl 4-(3-(difluoromethoxy)phenyl)-2,4-dioxobutanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 6.12 g (81.92%, reaction scale is 5 g); LCMS Calculated for C₁₂H₁₀F₂O₅: 272.05; Observed: 272.85 (M+1)⁺.

Synthesis of Methyl 4-(4-chlorophenyl)-2,4-dioxobutanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 32 g (82.13%, reaction scale is 25 g); LCMS Calculated for C₁₁H₉ClO₄: 240.02; Observed: 240.90 (M+1)⁺.

Synthesis of Methyl 4-(4-bromo-3-fluorophenyl)-2,4-dioxobutanoate (20)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 8 g (60.28%, reaction scale is 9.5 g); LCMS Calculated for C₁₁H₈BrFO₄: 301.96; Observed: 303.85 (M+2)⁺.

Synthesis of Methyl 5-(pyridin-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method A for the synthesis of cyclic sulfonamide described above to afford 1 g (19.68%, reaction scale is 3 g); LCMS Calculated for C₁₀H₉N₃O₄S: 267.03; LCMS observed: 268.15 (M+1)⁺.

Synthesis of Methyl 5-(5-fluoropyridin-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method A for the synthesis of cyclic sulfonamide described above to afford 2.5 g (80.64%, reaction scale is 2.5 g); LCMS Calculated for C₁₀H₈FN₃O₄S: 285.02; LCMS observed: 286.15 (M+1)⁺.

Synthesis of Methyl 5-(pyridin-3-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method A for the synthesis of cyclic sulfonamide described above to afford 3 g (46.58%, reaction scale is 5 g); LCMS Calculated for C₁₀H₉N₃O₄S: 267.03; LCMS observed: 267.95 (M+1)⁺.

Synthesis of Methyl 5-(4-fluorophenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method A for the synthesis of cyclic sulfonamide described above to afford 10.52 g (64%, reaction scale is 13 g); LCMS Calculated for C₁₁H₉FN₂O₄S: 284.03; LCMS observed: 285.15 (M+1)⁺.

Synthesis of Methyl 5-phenyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method for the synthesis of cyclic sulfonamide described above to afford 15.2 g (74%, reaction scale is 16 g); LCMS Calculated for C₁₁H₁₀N₂O₄S: 266.04; LCMS observed: 267.10 (M+1)⁺.

Synthesis of Methyl 5-(4-methoxyphenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method A for the synthesis of cyclic sulfonamide described above to afford 20 g (59.1%, reaction scale is 27 g); LCMS Calculated for C₁₂H₁₂N₂O₅S: 296.05; LCMS observed: 296.95 (M+1)⁺.

Synthesis of Methyl 5-(4-bromophenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method for the synthesis of cyclic sulfonamide described above to afford 33 g (68.39%, reaction scale is 40 g); LCMS Calculated for C₁₁H₉BrN₂O₄S: 343.95; LCMS observed: 346.95 (M+2)⁺.

Synthesis of Methyl 5-(3-methoxyphenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method for the synthesis of cyclic sulfonamide described above to afford 18 g (51%, reaction scale is 28 g); LCMS Calculated for C₁₂H₁₂N₂O₅S: 296.05; LCMS observed: 297.00 (M+1)⁺.

Synthesis of Methyl 5-(2-methoxyphenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method B for the synthesis of cyclic sulfonamide described above to afford 24 g (68.31%, reaction scale is 28 g; LCMS Calculated for C₁₂H₁₂N₂O₅S: 296.05; LCMS observed: 296.95 (M+1)⁺.

Synthesis of Methyl 5-(4-(trifluoromethyl)phenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method for the synthesis of cyclic sulfonamide described above to afford 35 g (71.79%, reaction scale is 40 g); LCMS Calculated for C₁₂H₉F₃N₂O₄S: 334.02; LCMS observed: 334.95 (M+1)⁺.

Synthesis of Methyl 5-(3,4-difluorophenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method B for the synthesis of cyclic sulfonamide described above to afford 20 g (53.43%, reaction scale is 30 g); LCMS Calculated for C₁₁H₈F₂N₂O₄S: 302.02; LCMS observed: 302.95 (M+1)⁺.

Synthesis of Methyl 5-(3-fluorophenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method B for the synthesis of cyclic sulfonamide described above to afford 25 g (66.03%, reaction scale is 30 g); LCMS Calculated for C₁₁H₉FN₂O₄S: 284.03; LCMS observed: 284.95 (M+1)⁺.

Synthesis of Methyl 5-(4-(trifluoromethoxy)phenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method for the synthesis of cyclic sulfonamide described above to afford 48 g (67.61%, reaction scale is 60 g); LCMS Calculated for C₁₂H₉F₃N₂O₅S: 350.02; LCMS observed: 350.95 (M+1)⁺.

Synthesis of Methyl 5-(3-(trifluoromethyl)phenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method for the synthesis of cyclic sulfonamide described above to afford 10 g (32.81%, reaction scale is 25 g); LCMS Calculated for C₁₂H₉F₃N₂O₄S: 334.02; LCMS observed: 335.05 (M+1)⁺.

Synthesis of Methyl 5-(3-chlorophenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method for the synthesis of cyclic sulfonamide described above to afford 12 g (53.3%, reaction scale is 18 g); LCMS Calculated for C₁₁H₉ClN₂O₄S: 300.00; LCMS observed: 300.90 (M+1)⁺.

Synthesis of Methyl 5-(3-(trifluoromethoxy)phenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method for the synthesis of cyclic sulfonamide described above to afford 13 g (crude, reaction scale is 15 g); LCMS Calculated for C₁₂H₉F₃N₂O₅S: 350.02; LCMS observed: 352 (M+1)⁺.

Synthesis of Methyl 5-(4-(difluoromethoxy)phenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method for the synthesis of cyclic sulfonamide described above to afford 9 g (crude, reaction scale is 12 g); LCMS Calculated for C₁₂H₁₀F₂N₂O₅S: 332.03; LCMS observed: 333 (M+1)⁺.

Synthesis of Methyl 5-(3-(difluoromethoxy)phenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method for the synthesis of cyclic sulfonamide described above to afford 5.10 g (69.76%, reaction scale is 6 g); LCMS Calculated for C₁₂H₁₀F₂N₂O₅S: 332.03; LCMS observed: 333 (M+1)⁺.

Synthesis of Methyl 5-(4-chlorophenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method for the synthesis of cyclic sulfonamide described above to afford 35 g (87%, reaction scale is 32 g); LCMS Calculated for C₁₁H₉ClN₂O₄S: 300.00; LCMS observed: 300.95 (M+1)⁺.

Synthesis of Methyl 5-(4-bromo-3-fluorophenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (21)

Title compound was synthesized using general method for the synthesis of cyclic sulfonamide described above to afford 7.6 g (79%, reaction scale is 8 g); LCMS Calculated for C₁₁H₈BrFN₂O₄S: 361.94; LCMS observed: 364.95 (M+2)⁺.

Synthesis of Methyl 2-methyl-5-(pyridin-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method A for alkylation described above to afford 0.8 g (76.04%, reaction scale is 1 g); LCMS Calculated for C₁₁H₁₁N₃O₄S: 281.05; LCMS observed: 282.20 (M+1)⁺.

Synthesis of Methyl 5-(5-fluoropyridin-2-yl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 1 g (95.32%, reaction scale is 1 g); LCMS Calculated for C₁₁H₁₀FN₃O₄S: 299.04; LCMS observed: 299.95 (M+1)⁺.

Synthesis of Methyl 2-methyl-5-(pyridin-3-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 1.6 g (50.6%, reaction scale is 3 g); LCMS Calculated for C₁₁H₁₁N₃O₄S: 281.05; LCMS observed: 282.20 (M+1)⁺.

Synthesis of Methyl 5-(4-fluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 0.5 g (95%, reaction scale is 0.5 g); LCMS Calculated for C₁₂H₁₁FN₂O₄S: 298.04; LCMS observed: 299.10 (M+1)⁺.

Synthesis of Methyl 5-(4-fluorophenyl)-2-(2-methoxyethyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 0.8 g (crude, reaction scale is 1 g); {Note: Isolated as a mixture of desired product and major trans-esterified side product. This mixture was carried forward in the next reaction (ester hydrolysis) without any separation). LCMS Calculated for C₁₄H₁₅FN₂O₅S: 342.07; LCMS observed: 343.20 (M+1)⁺.

Synthesis of Methyl 2-methyl-5-phenyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 2.4 g (46%, reaction scale is 5 g); LCMS Calculated for C₁₂H₁₂N₂O₄S: 280.05; LCMS observed: 281.15 (M+1)⁺.

Synthesis of Methyl 5-(4-methoxyphenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 5 g (95.9%, reaction scale is 5 g); LCMS Calculated for C₁₃H₁₄N₂O₅S: 310.06; LCMS observed: 310.95 (M+1)⁺.

Synthesis of Methyl 5-(4-bromophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 28 g (89.45%, reaction scale is 30 g); LCMS Calculated for C₁₂H₁₁BrN₂O₄S: 357.96; LCMS observed: 360.95 (M+1)⁺.

Synthesis of Methyl 5-(3-methoxyphenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 4.8 g (92%, reaction scale is 5 g); LCMS Calculated for C₁₃H₁₄N₂O₅S: 310.06; LCMS observed: 310.90 (M+1)⁺.

Synthesis of Methyl 5-(2-methoxyphenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 18 g (95.49%, reaction scale is 18 g); LCMS Calculated for C₁₃H₁₄N₂O₅S: 310.06; LCMS observed: 311.00 (M+1)⁺.

Synthesis of Methyl 2-methyl-5-(4-(trifluoromethyl)phenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 5 g (99.9%, reaction scale is 5 g); LCMS Calculated for C₁₃H₁₁F₃N₂O₄S: 348.04; LCMS observed: 348.90 (M+1)⁺.

Synthesis of Methyl 5-(3,4-difluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 4 g (76.48%, reaction scale is 5 g); LCMS Calculated for C₁₂H₁₀F₂N₂O₄S: 316.03; LCMS observed: 317.00 (M+1)⁺.

Synthesis of Methyl 5-(3-fluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 7 g (66.73%, reaction scale is 10 g); LCMS Calculated for C₁₂H₁₁FN₂O₄S: 298.04; LCMS observed: 299.00 (M+1)⁺.

Synthesis of Methyl 2-methyl-5-(4-(trifluoromethoxy)phenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 13.1 g (84.08%, reaction scale is 15 g); LCMS Calculated for C₁₃H₁₁F₃N₂O₄S: 364.03; LCMS observed: 364.90 (M+1)⁺.

Synthesis of Methyl 2-methyl-5-(3-(trifluoromethyl)phenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 7 g (67.24%, reaction scale is 10 g); LCMS Calculated for C₁₃H₁₁F₃N₂O₄S: 348.04; LCMS observed: 349.15 (M+1)⁺.

Synthesis of Methyl 5-(3-chlorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 3.6 g (69%, reaction scale is 5 g); LCMS Calculated for C₁₂H₁₁ClN₂O₄S: 314.01; LCMS observed: 314.95 (M+1)⁺.

Synthesis of Methyl 2-methyl-5-(3-(trifluoromethoxy)phenyl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 5 g (96.15%, reaction scale is 5 g); LCMS Calculated for C₁₃H₁₁F₃N₂O₅S: 364.03; LCMS observed: 365.05 (M+1)⁺.

Synthesis of Methyl 5-(4-(difluoromethoxy)phenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 5 g (95.96%, reaction scale is 5 g); LCMS Calculated for C₁₃H₁₂F₂N₂O₅S: 346.04; LCMS observed: 347.05 (M+1)⁺.

Synthesis of Methyl 5-(3-(difluoromethoxy)phenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 3 g (96.77%, reaction scale is 3 g); LCMS Calculated for C₁₃H₁₂F₂N₂O₅S: 346.04; LCMS observed: 347.05 (M+1)⁺.

Synthesis of Methyl 5-(4-chlorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 9.0 g (86%, reaction scale is 10 g); LCMS Calculated for C₁₂H₁₁ON₂O₄S: 314.01; LCMS observed: 314.90 (M+1)⁺.

Synthesis of Methyl 5-(4-bromo-3-fluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (22)

Title compound was synthesized using general method B for alkylation described above to afford 2.2 g (70.7%, reaction scale is 3 g); LCMS Calculated for C₁₂H₁₀BrFN₂O₄S: 375.95; LCMS observed: 378.95 (M+2)⁺.

N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(pyridin-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-031_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

N-(3-Chloro-4-fluorophenyl)-5-(5-fluoropyridin-2-yl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-032_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using Compound 22 and corresponding amine (see Table 1 for analytical data).

N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(pyridin-3-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-033_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

N-(3-chloro-4-fluorophenyl)-5-(4-fluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-112_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine. The crude intermediate confirmed by LCMS and carried forward to the next step.

N-(3-chloro-4-fluorophenyl)-2-methyl-5-phenyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-113_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

N-(3-chloro-4-fluorophenyl)-5-(4-methoxyphenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-200_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

5-(4-Bromophenyl)-N-(3-chloro-4-fluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-202_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

N-(3-chloro-4-fluorophenyl)-5-(3-methoxyphenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-204_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

N-(3-chloro-4-fluorophenyl)-5-(4-fluorophenyl)-2-(2-methoxyethyl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-210_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine. The reaction was monitored by LCMS and the crude intermediate carried forward to the next step.

N-(3-Bromo-4-fluorophenyl)-5-(4-fluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-211_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

5-(4-Fluorophenyl)-2-methyl-N-(3,4,5-trifluorophenyl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-212_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

N-(3-chloro-4-fluorophenyl)-5-(2-methoxyphenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-215_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(4-(trifluoromethyl)phenyl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-217_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

N-(3-Chloro-4-fluorophenyl)-5-(3,4-difluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-230_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

N-(3-Chloro-4-fluorophenyl)-5-(3-fluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-231_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine. The crude intermediate confirmed by LCMS and carried forward to the next step.

N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(4-(trifluoromethoxy)phenyl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-232_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

N-(3-chloro-4-fluorophenyl)-2-methyl-5-(3-(trifluoromethyl)phenyl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-259_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

N-(3-Chloro-4-fluorophenyl)-5-(3-chlorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-261_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(3-(trifluoromethoxy)phenyl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-262_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

N-(3-Chloro-4-fluorophenyl)-5-(4-(difluoromethoxy)phenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-263_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

N-(3-chloro-4-fluorophenyl)-5-(3-(difluoromethoxy)phenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-264_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

N-(3-Chloro-4-fluorophenyl)-5-(4-chlorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-265_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

5-(4-Bromo-3-fluorophenyl)-N-(3-chloro-4-fluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-283_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 22 and corresponding amine (see Table 1 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(pyridin-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-031, HBV-CSU-031-ISO-I & HBV-CSU-031-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-031_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(5-fluoropyridin-2-yl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-032, HBV-CSU-032-ISO-I & HBV-CSU-032-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-032_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(pyridin-3-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-033)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-033_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(4-fluorophenyl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-112, HBV-CSU-112-ISO-I & HBV-CSU-112-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-112_Int (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-phenyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-113-ISO-I & HBV-CSU-113-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-113_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(4-methoxyphenyl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-200)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-200_Int (see Table 2 for analytical data).

Cis-5-(4-Bromophenyl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-202)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-202_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(3-methoxyphenyl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-204)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-204_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(4-fluorophenyl)-2-(2-methoxyethyl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-210, HBV-CSU-210-ISO-I & HBV-CSU-210-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-210_Int (see Table 2 for analytical data).

Cis-N-(3-Bromo-4-fluorophenyl)-5-(4-fluorophenyl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-211, HBV-CSU-2H-ISO-I & HBV-CSU-2H-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-211_Int (see Table 2 for analytical data).

Cis-5-(4-Fluorophenyl)-2-methyl-N-(3, 4, 5-trifluorophenyl)-1,2,6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-212, HBV-CSU-212-ISO-I & HBV-CSU-212-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-212_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(2-methoxyphenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-215)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-215_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(4-(trifluoromethyl)phenyl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-217, HBV-CSU-217-ISO-I & HBV-CSU-217-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-217_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(3,4-difluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-230, HBV-CSU-230-ISO-I & HBV-CSU-230-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-230_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(3-fluorophenyl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-231, HBV-CSU-231-ISO-I & HBV-CSU-231-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-231_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(4-(trifluoromethoxy)phenyl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-232)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-232_Int (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(3-(trifluoromethyl)phenyl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-259, HBV-CSU-259-ISO-I & HBV-CSU-259-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-259_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(3-chlorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-261, HBV-CSU-261-ISO-I & HBV-CSU-261-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-261_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(3-(trifluoromethoxy)phenyl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-262, HBV-CSU-262-ISO-I & HBV-CSU-262-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-262_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(4-(difluoromethoxy)phenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-263, HBV-CSU-263-ISO-I & HBV-CSU-263-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-263_Int (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(3-(difluoromethoxy)phenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-264, HBV-CSU-264-ISO-I & HBV-CSU-264-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-264_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(4-chlorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-265)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-265_Int (see Table 2 for analytical data).

Cis-5-(4-Bromo-3-fluorophenyl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-283)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-283_Int (see Table 2 for analytical data).

Scheme 7:

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-2-(2-hydroxyethyl)-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-041)

N-(3-chloro-4-fluorophenyl)-2-(2-oxoethyl)-5-(thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-041_Int)

To a stirred solution of HNB-CSU-40_Int (0.2 g, 0.47 mmol) in DCM (10 mL) at 0° C., NMO (0.169 g, 1.41 mmol) was added and stirred for 10 min. To this solution, OsO₄ in butanol (0.035 g, 0.141 mmol) was added at 0° C. and stirred at room temperature for 1 h. After completion, the reaction mixture was concentrated under reduced pressure. The crude residue obtained was dissolved in 10 mL of THF:H₂O (1:1) mixture, NaIO₄ (0.278 g, 1.41 mmol) was added and the reaction mixture was stirred at room temperature for 3 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was concentrated under reduced pressure and the crude compound obtained was purified by silica gel column chromatography using 15% EtOAc/hexane to afford the desired compound (0.1 g, 49.75%) as an off-white solid. TLC for aldehyde: 40% EtOAc/hexanes (R_f: 0.3); The reaction monitored by TLC (DNP stain) and the crude intermediate was carried forward to the next step without any purification.

Cis-N-(3-Chloro-4-fluorophenyl)-2-(2-hydroxyethyl)-5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-041)

The above titled compound has been synthesized by following the general procedure described above for reduction by using HBV-CSU-041_Int (see Table 2 for analytical data).

Scheme 8:

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-2,5-dimethyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-050-ISO-I & HBV-CSU-050-ISO-II)

Synthesis of Methyl 5-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (24)

Title compound was synthesized using general method for the synthesis of cyclic sulfonamide described above to afford 5.95 g (84.03%, reaction scale is 5 g); LCMS Calculated for C₆H₈N₂O₄S: 204.02; LCMS observed: 204.85 (M+1)⁺.

Synthesis of Methyl 2, 5-dimethyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (25)

Title compound was synthesized using general method A for alkylation described above to afford 3.57 g (83.6%, reaction scale is 4 g); LCMS Calculated for C₇H₁₀N₂O₄S: 218.04; LCMS observed: 218.90 (M+1)⁺.

Synthesis of N-(3-chloro-4-fluorophenyl)-2,5-dimethyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-050_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using Compound 25 and corresponding amine (see Table 1 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2, 5-dimethyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-050-ISO-I & HBV-CSU-050-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-050_Int (see Table 2 for analytical data).

Scheme 9:

Synthetic Scheme for Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(1-methyl-1H-pyrazol-5-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-054, HBV-CSU-054-ISO-I & HBV-CSU-054-ISO-II)

Synthesis of N-methoxy-N, 1-dimethyl-1H-pyrazole-5-carboxamide (27)

To a stirred solution of compound 26 (12 g, 95.23 mmol) in CH₂Cl₂ (600 mL) under inert atmosphere were added N, O-dimethylhydroxylamine hydrochloride (10.26 g, 104.76 mmol), EDCI.HCl (19.2 g, 100.00 mmol), DMAP (12.8 g, 104.91 mmol), and N-methylmorpholine (12.8 mL, 11.54 mmol) at 0° C., followed by warming to room temperature and stirring for 16 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was poured into ice-cold water and extracted using EtOAc. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel flash column chromatography using 10% EtOAc/hexanes to afford compound 27 (12 g, 75%) as brown liquid. TLC: 20% EtOAc/hexanes (R_f: 0.8); ¹H NMR (400 MHz, CDCl₃): δ 7.48 (d, J=2.0 Hz, 1H), 6.77 (d, J=2.0 Hz, 1H), 4.13 (s, 3H), 3.66 (s, 3H), 3.36 (s, 3H); LCMS Calculated for C₇H₁₁N₃O₂: 169.09; Observed: 169.9 (M+1)⁺.

Synthesis of 1-(1-methyl-1H-pyrazol-5-yl) ethan-1-one (28)

To a stirred solution of compound 27 (6 g, 35.50 mmol) in anhydrous diethyl ether (75 mL) under inert atmosphere was added methyl magnesium bromide (23.6 mL, 71.00 mmol, 3 M sol. in diethyl ether) dropwise for 15 min at −40° C., followed by warming to room temperature and stirring for 16 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with saturated ammonium chloride solution (50 mL) and extracted with diethyl ether. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford compound 28 (5 g, crude) as pale brown liquid. TLC: 20% EtOAc/hexanes (R_f: 0.4); ¹H NMR (400 MHz, CDCl₃): δ 7.46 (d, J=2.0 Hz, 1H), 6.83 (d, J=2.1 Hz, 1H), 4.16 (s, 3H), 2.52 (s, 3H); LCMS Calculated for C₆H₈N₂O: 124.06; Observed: 124.9 (M+1)⁺.

Synthesis of Methyl 4-(1-methyl-1H-pyrazol-5-yl)-2, 4-dioxobutanoate (29)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 7 g (94%, over 2 steps, reaction scale is 5 g) as pale yellow solid. TLC: 20% EtOAc/hexanes (R_f: 0.3); ¹H NMR (400 MHz, DMSO-d₆): δ 13.33 (br.s, 1H), 7.59 (d, J=1.8 Hz, 1H), 7.38 (br.s, 1H), 6.93 (s, 1H), 4.13 (s, 3H), 3.85 (s, 3H); LCMS Calculated for C₉H₁₀N₂O₄: 210.06; Observed: 210.9 (M)⁺.

Synthesis of Methyl 5-(1-methyl-1H-pyrazol-5-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (30)

Title compound was synthesized using general method A for the synthesis of cyclic sulfonamide described above to afford 2 g (44%, reaction scale is 3.5 g) as pale yellow solid. TLC: 5% MeOH/CH₂Cl₂ (R_f: 0.2); ¹H NMR (400 MHz, DMSO-d₆): δ 7.49 (d, J=2.0 Hz, 1H), 6.86 (d, J=2.0 Hz, 1H), 6.55 (s, 1H), 4.11 (s, 3H), 3.81 (s, 3H).

Synthesis of Methyl 2-methyl-5-(1-methyl-1H-pyrazol-5-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (31)

Title compound was synthesized using general method A for alkylation described above to afford 50 mg (12%, reaction scale is 400 mg) as an off-white solid. TLC: 5% MeOH/CH₂Cl₂ (R_f: 0.4); ¹H NMR (400 MHz, DMSO-d₆): δ 7.64 (d, J=2.1 Hz, 1H), 7.33 (d, J=2.3 Hz, 1H), 7.17 (s, 1H), 4.16 (s, 3H), 3.94 (s, 3H), 3.53 (s, 3H); LCMS Calculated for C₁₀H₁₂N₄O₄S: 284.06; Observed: 285.1 (M+1)⁺.

Synthesis of N-(3-chloro-4-fluorophenyl)-2-methyl-5-(1-methyl-1H-pyrazol-5-yl)-2H-1, 2, 6-thiadiazine-3-carboxamide 1, 1-dioxide (HBV-CSU-054_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 31 and corresponding amine (see Table 1 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(1-methyl-1H-pyrazol-5-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-054, HBV-CSU-054-ISO-I & HBV-CSU-054-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-054_Int (see Table 2 for analytical data).

Scheme 10:

Synthetic Scheme for Cis-N-(3-Chloro-4-fluorophenyl)-5-(isoxazol-3-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-055, HBV-CSU-055-ISO-I & HBV-CSU-055-II)

Synthesis of N-methoxy-N-methylisoxazole-3-carboxamide (33)

To a stirred solution isoxazole-3-carboxylic acid 32 (7 g, 61.94 mmol) in CH₂Cl₂ (200 mL) under inert atmosphere were added N, O-dimethylhydroxylamine hydrochloride (6.64 g, 68.14 mmol), EDCI.HCl (13 g, 68.14 mmol), DMAP (7.6 g, 61.94 mmol), and N-methylmorpholine (9.5 mL, 92.92 mmol) at 0° C., followed by warming to room temperature and stirred for 16 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was poured into ice-cold water, extracted with CH₂Cl₂. The combined organic extracts were washed with 2 N HCl, dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 3% MeOH/CH₂Cl₂ to afford compound 33 (6 g, 63%) as brown liquid. TLC: 5% MeOH/CH₂Cl₂ (R_f: 0.8); ¹H NMR (400 MHz, DMSO-d₆): δ 9.08 (d, J=1.6 Hz, 1H), 6.86 (d, J=1.3 Hz, 1H), 3.68 (s, 3H), 3.31 (s, 3H).

Synthesis of 1-(isoxazol-3-yl) ethan-1-one (34)

To a stirred solution of compound 33 (6 g, 38.46 mmol) in dry diethyl ether (100 mL) under inert atmosphere was added methyl magnesium bromide (12.8 mL, 38.46 mmol, 3 M sol. in diethyl ether) dropwise for 10 min at −40° C., followed by warming to 0° C. and stirred for 2 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with saturated ammonium chloride solution at 0° C. and stirred for 15 min, then extracted with diethyl ether. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford compound 34 (3 g, 70%) as pale brown liquid. TLC: 20% EtOAc/hexanes (R_f: 0.8); ¹H NMR (400 MHz, DMSO-d₆): δ 9.13 (d, J=1.8 Hz, 1H), 6.92 (d, J=1.8 Hz, 1H), 2.60 (s, 3H).

Synthesis of Methyl (E/Z)-4-hydroxy-4-(isoxazol-3-yl)-2-oxobut-3-enoate (35)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 2 g (38, reaction scale is 3 g) as off-white sticky solid. TLC: 5% MeOH/CH₂Cl₂ (R_f: 0.4); ¹H NMR (400 MHz, DMSO-d₆): δ 9.19 (d, J=1.5 Hz, 1H), 7.08 (s, 1H), 5.24 (br. s, 2H), 3.85 (s, 3H).

Synthesis of Methyl 5-(isoxazol-3-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (36)

Title compound was synthesized using general method A for the synthesis of cyclic sulfonamide described above to afford 1.2 g (crude, reaction scale is 1 g) as off-white solid. TLC: 5% MeOH/CH₂Cl₂ (R_f: 0.4). The crude material was used as such in the next reaction without further characterization.

Synthesis of Methyl 5-(isoxazol-3-yl)-2-methyl-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (37)

Title compound was synthesized using general method A for alkylation described above to afford 350 mg (26%, reaction scale is 1.2 g) as an off-white solid. TLC: 10% MeOH/CH₂Cl₂ (R_f: 0.4); ¹H NMR (500 MHz, DMSO-d₆): δ 9.26 (s, 1H), 7.27 (s, 1H), 7.21 (s, 1H), 3.94 (s, 3H), 3.60 (s, 3H).

Synthesis of N-(3-chloro-4-fluorophenyl)-5-(isoxazol-3-yl)-2-methyl-2H-1, 2, 6-thiadiazine-3-carboxamide 1, 1-dioxide (HBV-CSU-055_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 37 and corresponding amine (see Table 1 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(isoxazol-3-yl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-055, HBV-CSU-055-ISO-I & HBV-CSU-055-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-055_Int (see Table 2 for analytical data).

Scheme 11:

Synthetic Scheme for Cis-N-(3-chloro-4-fluorophenyl)-5-(isothiazol-3-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-056, HBV-CSU-056-ISO-I & HBV-CSU-056-ISO-II)

Synthesis of 3-methylisothiazole (39)

To a stirred solution of but-3-yn-2-one 38 (17 g, 249.70 mmol) in H₂O (100 mL) was added hydroxylamine-O-sulfonic acid (29.1 g, 257.23 mmol) at 0° C. and stirred for 30 min. To this was added sodium bicarbonate (23.72 g, 281.9 mmol) portion wise for 20 min at 0° C., followed by dropwise addition of sodium hydrogen sulfide dihydrate (26 g, 282.2 mmol) in H₂O (170 mL) at 0° C. for 15 min, then warming to room temperature and stirring for 16 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was diluted with water and extracted with diethyl ether. The combined organic extracts were dried over anhydrous sodium sulfate and concentrated in vacuo at 20° C. to afford compound 39 (10 g, 40%) as colorless syrup. TLC: 15% EtOAc/hexanes (R_f: 0.5); ¹H-NMR (DMSO-d₆, 400 MHz): δ 8.96 (d, J=4.5 Hz, 1H), 7.20 (d, J=4.5 Hz, 1H), 2.45 (s, 3H).

Synthesis of isothiazole-3-carboxylic Acid (40)

To a stirred solution of compound 39 (10 g, 100.85 mmol) in concentrated sulfuric acid (300 mL) under inert atmosphere was added chromium (VI) oxide (30.25 g, 302.57 mmol) portion wise at 0° C., followed by warming to room temperature and stirring for 16 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with ice-cold water (3 L) slowly and extracted with diethyl ether (10×600 mL). The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford crude compound 40 (3 g, 23%) as white solid. TLC: 20% EtOAc/hexanes (R_f: 0.1). ¹H-NMR (DMSO-d₆, 400 MHz): δ 10.95 (br.s, 1H), 9.16 (d, J=4.6 Hz, 1H), 7.80 (d, J=4.6 Hz, 1H); LCMS Calculated for C₄H₃NO₂S: 128.99; Observed: 130.4 (M+1)⁺.

Synthesis of N-methoxy-N-methylisothiazole-3-carboxamide (41)

To a stirred solution compound 40 (3 g, 23.25 mmol) in CH₂Cl₂ (60 mL) under inert atmosphere were added EDCI.HCl (4.9 g, 25.58 mmol), DMAP (2.8 g, 23.25 mmol), N-methylmorpholine (7.65 mL, 69.76 mmol) and N, O-dimethylhydroxylamine hydrochloride (2.72 g, 27.90 mmol) at 0° C., followed by warming to room temperature and stirring for 16 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was diluted with ice-cold water and extracted with CH₂Cl₂. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel flash column chromatography using 40-45% EtOAc/hexanes to afford compound 41 (2.5 g, 63%) as brown syrup. TLC: 40% EtOAc/hexanes (R_f: 0.5); ¹H NMR (400 MHz, DMSO-d₆): δ 9.15 (d, J=4.8 Hz, 1H), 7.63 (d, J=4.4 Hz, 1H), 3.69 (s, 3H), 3.33 (s, 3H); LCMS Calculated for C₆H₇NOS: 141.02; Observed: 142.0 (M+1)⁺. LC-MS: 98.67%; 172.9 (M+1)⁺.

Synthesis of 1-(isothiazol-3-yl) ethan-1-one (42)

To a stirred solution of compound 41 (2.5 g, 14.53 mmol) in anhydrous diethyl ether (25 mL) under inert atmosphere was added methyl magnesium bromide (58 mL, 58.13 mmol, 3 M sol. in diethyl ether) dropwise for 20 min at −40° C., followed by warming to 0° C. and stirring for 2 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with saturated ammonium chloride solution at 0° C. and extracted with diethyl ether. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo below 20° C. to afford crude compound 42 (1.8 g, 98%) as yellow liquid. TLC: 30% EtOAc/hexanes (R_f: 0.8); ¹H NMR (500 MHz, DMSO-d₆): δ 9.15 (d, J=4.5 Hz, 1H), 7.80 (d, J=4.5 Hz, 1H), 2.62 (s, 3H); LCMS Calculated for C₅H₅NOS: 127.01; Observed: 128.4 (M+1)⁺.

Synthesis of Methyl (E/Z)-4-hydroxy-4-(isothiazol-3-yl)-2-oxobut-3-enoate (43)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 1.5 g (50%, reaction scale is 1.8 g) as yellow solid. TLC: 5% MeOH/CH₂Cl₂ (R_f: 0.4); ¹H NMR (400 MHz, DMSO-d₆): δ 9.24 (d, J=4.6 Hz, 1H), 7.95 (d, J=4.4 Hz, 1H), 7.27-7.24 (m, 1H), 3.86 (s, 3H); LCMS Calculated for C₈H₇NO₄S: 213.01; Observed: 214.2 (M+1)⁺.

Synthesis of Methyl 5-(isothiazol-3-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (44)

Title compound was synthesized using general method A for the synthesis of cyclic sulfonamide described above to afford 1.2 g (63%, reaction scale is 1.5 g) as off-white solid. TLC: 5% MeOH/CH₂Cl₂ (R_f: 0.1); ¹H NMR (400 MHz, DMSO-d₆): δ 9.16 (d, J=4.6 Hz, 1H), 7.90 (d, J=4.6 Hz, 1H), 7.06 (s, 1H), 3.83 (s, 3H); LCMS Calculated for C₈H₇N₃O₄S₂: 272.99; LCMS observed: 271.9 (M−1)⁻.

Synthesis of Methyl 5-(isothiazol-3-yl)-2-methyl-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (45)

Title compound was synthesized using general method A for alkylation described above to afford 450 mg (61%, reaction scale is 700 mg) as an off-white solid. TLC: 40% EtOAc/hexanes (R_f: 0.6); ¹H NMR (400 MHz, DMSO-d₆): δ 9.28 (d, J=4.8 Hz, 1H), 8.04 (d, J=4.8 Hz, 1H), 7.50 (s, 1H), 3.94 (s, 3H), 3.58 (s, 3H).

Synthesis of N-(3-chloro-4-fluorophenyl)-5-(isothiazol-3-yl)-2-methyl-2H-1, 2, 6-thiadiazine-3-carboxamide 1, 1-dioxide (HBV-CSU-056_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 45 and corresponding amine (see Table 1 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(isothiazol-3-yl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-056, HBV-CSU-056-ISO-I & HBV-CSU-056-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-055_Int (see Table 2 for analytical data).

Scheme 12:

Synthetic scheme for Cis-N-(3-chloro-4-fluorophenyl)-5-(isothiazol-5-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-057, HBV-CSU-057-ISO-I & HBV-CSU-057-ISO-II)

Synthesis of N-methoxy-N-methylisothiazole-5-carboxamide (47)

To a stirred solution isothiazole-5-carboxylic acid 46 (1.75 g, 13.56 mmol) in CH₂Cl₂ (50 mL) under inert atmosphere were added N, O-dimethylhydroxylamine (1.45 g, 14.92 mmol), EDCI.HCl (2.85 g, 14.92 mmol), DMAP (1.66 g, 13.56 mmol) and N-methylmorpholine (4.1 mL, 40.69 mmol) at 0° C., followed by warming to room temperature and stirring for 16 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was poured into ice-cold water, extracted with CH₂Cl₂. The combined organic extracts were dried over sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 2% MeOH/CH₂Cl₂ to afford compound 47 (1.2 g, 52%) as brown syrup. TLC: 5% MeOH/CH₂Cl₂ (R_f: 0.2); ¹H NMR (400 MHz, DMSO-d₆): δ 8.64 (d, J=1.8 Hz, 1H), 7.96 (d, J=1.8 Hz, 1H), 3.82 (s, 3H), 3.33 (s, 3H); LCMS Calculated for C₆H₈N₂O₂S: 172.03; Observed: 173.1 (M+1)⁺.

Synthesis of 1-(isothiazol-5-yl) ethan-1-one (48)

To a stirred solution of compound 47 (1.2 g, 6.97 mmol) in anhydrous diethyl ether (30 mL) under inert atmosphere was added methyl magnesium bromide (6.97 mL, 20.93 mmol, 3 M sol. in diethyl ether) dropwise for 10 min at −40° C., followed by warming to 0° C. and stirring for 2 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with saturated ammonium chloride solution and extracted with diethyl ether. The combined organic extracts were dried over sodium sulfate, filtered and concentrated in vacuo to afford compound 48 (800 mg, crude) as yellow liquid. TLC: 20% EtOAc/hexanes (R_f: 0.8); ¹H NMR (400 MHz, DMSO-d₆): δ 8.75 (d, J=1.9 Hz, 1H), 8.04 (d, J=1.8 Hz, 1H), 2.64 (s, 3H).

Synthesis of Methyl (E/Z)-4-hydroxy-4-(isothiazol-5-yl)-2-oxobut-3-enoate (49)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 600 mg (45%, reaction scale is 800 mg) as a yellow solid. TLC: 5% MeOH/CH₂Cl₂ (R_f: 0.4); ¹H NMR (400 MHz, DMSO-d₆): δ 8.78 (d, J=1.9 Hz, 1H), 8.29 (br.s, 1H), 6.98 (br.s, 1H), 3.86 (s, 3H).

Synthesis of Methyl 5-(isothiazol-5-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (50)

Title compound was synthesized using general method A for the synthesis of cyclic sulfonamide described above to afford 300 mg (36%, reaction scale is 650 mg) as yellow solid.

TLC: 10% MeOH/CH₂Cl₂ (R_f: 0.1); ¹H NMR (400 MHz, DMSO-d₆): δ 8.59 (d, J=1.9 Hz, 1H), 7.93 (d, J=1.9 Hz, 1H), 6.73 (br.s, 1H), 6.60 (s, 1H), 3.80 (s, 3H); LCMS Calculated for C₁₃H₁₀N₄O₄S₂: 272.99; LCMS observed: 274.2 (M+1)⁺.

Synthesis of Methyl 5-(isothiazol-5-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (51)

Title compound was synthesized using general method A for alkylation described above to afford 85 mg (32%, reaction scale is 250 mg) as an off-white solid. TLC: 30% EtOAc/hexanes (R_f: 0.48; ¹H NMR (400 MHz, DMSO-d₆): δ 8.80 (d, J=1.9 Hz, 1H), 8.37 (d, J=1.9 Hz, 1H), 7.37 (s, 1H), 3.96 (s, 3H), 3.58 (s, 3H); LCMS Calculated for C₁₃H₁₀N₄O₄S₂: 287.00; LCMS observed: 288.1 (M+1)⁺.

Synthesis of N-(3-chloro-4-fluorophenyl)-5-(isothiazol-5-yl)-2-methyl-2H-1, 2, 6-thiadiazine-3-carboxamide 1, 1-dioxide (HBV-CSU-057_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 51 and corresponding amine (see Table 1 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(isothiazol-5-yl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-057)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-057_Int (see Table 2 for analytical data).

Scheme 13:

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-2-(2-(methylsulfonyl)ethyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-73, HBV-CSU-73-ISO-I & HBV-CSU-73-ISO-II)

Synthesis of N-(3-chloro-4-fluorophenyl)-2-(2-(methylsulfonyl) ethyl)-5-(thiazol-2-yl)-2H-1, 2, 6-thiadiazine-3-carboxamide 1, 1-dioxide (HBV-CSU-073_Int)

To a stirred solution of HBV-CSU-109_Int (1 g, 2.17 mmol) in 1,2-dichloro ethane: CH₃CN: H₂O (1:1:2, 20 mL) were added sodium metaperiodate (1.3 g, 6.07 mmol) and ruthenium chloride (22.54 mg, 0.10 mmol) at room temperature and stirred for 3 h. The reaction was monitored by TLC. After completion, the volatiles were removed in vacuo. The residue was diluted with water and extracted using EtOAc. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 1% MeOH/CH₂Cl₂. The obtained solid was washed with diethyl ether and dried in vacuo to afford HBV-CSU-073_Int (560 mg, 53%) as an off-white solid. TLC: 5% MeOH/CH₂Cl₂ (R_f: 0.5) (see Table 1 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-(2-(methylsulfonyl)ethyl)-5-(thiazol-2-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-073

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-073_Int (see Table 2 for analytical data).

Scheme 14:

Synthesis of Cis-N-(3-Chloro-4-fluorophenyl)-2-(2-(dimethylamino)ethyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-074) & Cis-N-(3-Chloro-4-fluorophenyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-096)

Cis-N-(3-Chloro-4-fluorophenyl)-2-(2-(dimethylamino)ethyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-074)

To a stirred solution of HBV-CSU-096 (20 mg, 0.051 mmol.) in CH₃CN (0.5 mL) at 0° C., K₂CO₃ (14 mg, 0.102 mmol) and 2-chloro-N,N-dimethylethan-1-amine hydrochloride (7 mg, 0.051 mmol) were added. The reaction mixture was stirred at room temperature for 12 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was diluted with ice cold water. The obtained solid was filtered and the filtrate was extracted with ethyl acetate. The combined organic layers were washed with water and brine; dried over anhydrous sodium sulphate and concentrated in vacuo. The crude compound was purified by silica gel column chromatography to afford the compound HBV-CSU-074 (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-096, HBV-CSU-096-ISO-I & HBV-CSU-096-ISO-II)

To a stirred solution of compound HBV-CSU-108 (0.14 g, 0.274 mmol) in DCM (1 mL) at 0° C., TFA (5 mL) was added and stirred at room temperature for 30 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was concentrated under reduced pressure. The crude compound was purified by silica gel column chromatography to afford the desired compound as HBV-CSU-096 (80 mg, 76%) as an off white solid. TLC: 40% EtOAc/hexanes (R_f: 0.3) (see Table 2 for analytical data).

Scheme 15:

Synthesis of Cis-N-(3-Chloro-4-fluorophenyl)-2-(3-hydroxypropyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-078, HBV-CSU-078-ISO-I & HBV-CSU-078-ISO-II)

To a stirred solution of compound HBV-CSU-077 (50 mg, 0.108 mmol) in DCM (5 mL) at −40° C., BBr₃ (0.054 g, 0.216 mmol) was added and stirred at room temperature for 4 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was quenched with sat. NaHCO₃ solution and extracted with DCM. The combined organic layers were dried over anhydrous sodium sulphate and concentrated under reduced pressure. The crude compound was purified by silica gel column chromatography to afford the desired compound as HBV-CSU-078 (0.042 g, 88%) as a white solid TLC: 40% EtOAc/hexanes (R_f: 0.1) (see Table 2 for analytical data).

Scheme 16:

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-2-(2-(methylsulfonyl)ethyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-092, HBV-CSU-092-ISO-I & HBV-CSU-092-ISO-II)

2-(2-(1H-1,2,3-Triazol-4-yl)ethyl)-N-(3-chloro-4-fluorophenyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-092_Int)

To a stirred solution of HBV-CSU-090_Int (300 mg, 0.68 mmol) in a mixture of DMF: H₂O (3:1, 8 mL) were added copper (II) sulfate pentahydrate (17 mg, 0.068 mmol) and L-ascorbic acid sodium salt (543 mg, 2.73 mmol) and azidotrimethylsilane (0.14 mL, 1.02 mmol) in 10° C., followed by warming to room temperature and stirring for 36 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was diluted with water and extracted using EtOAc. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel flash column chromatography 1-2% MeOH/CH₂Cl₂ to afford HBV-CSU-092_Int (80 mg, 24%) as an off-white solid. TLC: 40% EtOAc/hexanes (R_f: 0.3) (see Table 1 for analytical data).

Cis-2-(2-(1H-1,2,3-Triazol-4-yl)ethyl)-N-(3-chloro-4-fluorophenyl)-5-(thiazol-2-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-092, HBV-CSU-092-ISO-I, HBV-CSU-092-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-092_Int (see Table 2 for analytical data).

Scheme 17:

Cis-N-(3-Chloro-4-fluorophenyl)-2-(cyanomethyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-093)/Cis-2-(3-((3-Chloro-4-fluorophenyl)carbamoyl)-1,1-dioxido-5-(thiazol-2-yl)-1,2,6-thiadiazinan-2-yl)acetic Acid (HBV-CSU-110) & Cis-2-(3-((3-Chloro-4-fluorophenyl)carbamoyl)-1,1-dioxido-5-(thiazol-2-yl)-1,2,6-thiadiazinan-2-yl)acetic acid (HBV-CSU-111)

Methyl 2-(2-(tert-butoxy)-2-oxoethyl)-5-(thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (52)

Title compound was synthesized using general method B for alkylation described above to afford 6 g (84.74%, reaction scale is 5 g); LCMS Calculated for C₁₄H₁₇N₃O₆S₂: 387.06; LCMS observed: 332.15 (M-55)⁺.

Synthesis of tert-butyl 2-(3-((3-chloro-4-fluorophenyl) carbamoyl)-1,1-dioxido-5-(thiazol-2-yl)-2H-1,2,6-thiadiazin-2-yl)acetate (53)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 52 and corresponding amine. The ¹H NMR hints for the desired alkylation (Note: the NMR indicated contamination with a hydrazide side product).

tert-Butyl 2-(3-((3-chloro-4-fluorophenyl)carbamoyl)-1,1-dioxido-5-(thiazol-2-yl)-1,2,6-thiadiazinan-2-yl)acetate (54)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding Compound 53. The crude material was directly used in the next step.

Cis-N-(3-Chloro-4-fluorophenyl)-2-(cyanomethyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-093, HBV-CSU-093-ISO-I & HBV-CSU-093-ISO-II)

To a stirred solution of HBV-CSU-111 (50 mg, 0.111 mmol) in DCM (2 mL) at 0° C., TFAA (0.046 mL, 0.33 mmol) was added and stirred at same temperature for 20 min. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was concentrated under reduced pressure; water was added and extracted with DCM. The combined organic extracts were dried over anhydrous sodium sulphate, filtered, concentrated under vacuo to afford solid material which was triturated with diethyl ether to afford the desired compound HBV-CSU-093 (0.11 g, 38.32%) as a white solid. TLC: 5% MeOH/DCM (R_f: 0.2) (see Table 2 for analytical data).

Cis-2-(3-((3-Chloro-4-fluorophenyl)carbamoyl)-1,1-dioxido-5-(thiazol-2-yl)-1,2,6-thiadiazinan-2-yl)acetic Acid (HBV-CSU-110)

To a stirred solution of compound 54 (0.9 g, 1.78 mmol) in DCM (5 mL) at 0° C., TFA (15 mL) was added and stirred at room temperature for 6 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was concentrated under reduced pressure. The crude compound was washed with diethyl ether and purified by prep. HPLC to afford the desired compound HBV-CSU-110 (30 mg, 23%) as a white solid. TLC: 40% EtOAc/hexanes (R_f: 0.1) (see Table 2 for analytical data).

Cis-2-(3-((3-Chloro-4-fluorophenyl)carbamoyl)-1,1-dioxido-5-(thiazol-2-yl)-1,2,6-thiadiazinan-2-yl)acetic acid (HBV-CSU-111)

To a stirred solution of compound HBV-CSU-110 (0.16 g, 0.357 mmol) in DMF (10 mL) at 0° C., DIPEA (0.138 g, 1.07 mmol) and HATU (0.176 g, 0.464 mmol) were added and stirred for 15 min. To this solution, NH₄Cl (0.056 g, 1.07 mmol) was added. The reaction mixture was stirred at room temperature for overnight. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was diluted with ice cold water and extracted with DCM. The combined organic layers were dried over anhydrous sodium sulphate and concentrated under reduced pressure to afford a crude compound. The crude compound was purified by silica gel column chromatography to afford the desired compound as HBV-CSU-111 (0.1 g, 63%) as a white solid. TLC: 10% MeOH/DCM (R_f: 0.3) (see Table 2 for analytical data).

Scheme 18:

Synthesis of Cis-N-(3-Chloro-4-fluorophenyl)-2-(2-hydroxyethyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-097, HBV-CSU-097-ISO-I & HBV-CSU-097-ISO-II)

To a stirred solution of HBV-CSU-058 (0.25 g, 0.558 mmol) in DCM (10 mL) at −40° C., BBr₃ (0.104 mL, 1.11 mmol) was added and stirred at room temperature for 4 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was quenched with sat. NaHCO₃ solution and extracted with DCM. The combined organic layers were dried over anhydrous sodium sulphate and concentrated under reduced pressure. The crude compound was purified by silica gel column chromatography to afford the desired compound as HBV-CSU-097 (0.06 g, 24.79%) as an off white solid. TLC: 5% MeOH/DCM (R_f: 0.2) (see Table 2 for analytical data).

Scheme 19:

Synthesis of Cis-N-(3-Chloro-4-fluorophenyl)-2-(3-(diethylamino)propyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-101)/Cis-N-(3-Chloro-4-fluorophenyl)-2-(3-(pyrrolidin-1-yl)propyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-102) & Cis-N-(3-Chloro-4-fluorophenyl)-2-(3-morpholinopropyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-103)

2-(3-Bromopropyl)-N-(3-chloro-4-fluorophenyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (55)

To a stirred solution of HBV-CSU-077 (2 g, 4.31 mmol) in DCM (20 mL) at −40° C. under Ar atmosphere, BBr₃ (2.02 mL, 21.59 mmol) was added drop wise. The resulting reaction mixture was stirred at room temperature for 5 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was quenched with sat. NaHCO₃ solution and extracted with DCM. The combined organic layers were washed with water and brine, dried over anhydrous sodium sulphate, and concentrated in vacuo. The crude compound was purified by silica gel column chromatography using 2% MeOH/DCM to afford compound 55 (1.35 g, 61.08%) as a brown colored oil. LCMS Calculated for C₁₆H₁₇BrClFN₄O₃S₂: 509.16; Observed: 513.35 (M+4)⁺.

Cis-N-(3-Chloro-4-fluorophenyl)-2-(3-(diethylamino)propyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-101-ISO-I & HBV-CSU-101-ISO-II)

To a stirred solution of compound 55 (0.3 g, 0.585 mmol.) in DMF (5 mL) at 0° C., K₂CO₃ (0.161 g, 1.17 mmol) and diethylamine (0.042 g, 0.585 mmol) were added. The reaction mixture was stirred at room temperature for 12 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was diluted with ice cold water. The obtained solid was filtered and the filtrate was extracted with ethyl acetate. The combined organic layers were washed with water and brine; dried over anhydrous sodium sulphate, and concentrated in vacuo. The crude compound was purified by prep. HPLC to afford the compound HBV-CSU-101 (0.26 g, 75.80%) as a white solid. (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-(3-(pyrrolidin-1-yl)propyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-102, HBV-CSU-102-ISO-I & HBV-CSU-102-ISO-II)

To a stirred solution of compound 55 (0.5 g, 0.976 mmol.) in DMF (5 mL) at 0° C., K₂CO₃ (0.404 g, 2.92 mmol) and pyrrolidine (0.138 g, 1.95 mmol) were added. The reaction mixture was stirred at room temperature for 12 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was diluted with ice cold water. The obtained solid was filtered and the filtrate was extracted with ethyl acetate. The combined organic layers were washed with water and brine, dried over anhydrous sodium sulphate, and concentrated in vacuo. The crude compound was purified by prep. HPLC to afford the compound HBV-CSU-102 (Cis isomer) (0.12 g, 24.53%) as a white solid. TLC: 5% MeOH/DCM (R_f: 0.1) (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-(3-morpholinopropyl)-5-(thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-103)

To a stirred solution of compound 55 (0.5 g, 0.976 mmol.) in DMF (5 mL) at 0° C., K₂CO₃ (0.404 g, 2.92 mmol) and morpholine (0.169 g, 1.95 mmol) were added. The reaction mixture was stirred at room temperature for 12 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was diluted with ice cold water. The obtained solid was filtered and the filtrate was extracted with ethyl acetate. The combined organic layers were washed with water and brine, dried over anhydrous sodium sulphate, and concentrated in vacuo. The crude compound was purified by prep. HPLC to afford the compound HBV-CSU-103 (0.16 g, 31.74%) as a white solid. TLC: 5% MeOH/DCM (R_f: 0.1) (see Table 2 for analytical data).

Scheme 20:

General Synthetic Scheme for 5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide Derivatives with 5-substituted Thiophene & Aniline Variations

Target	Coupling reaction	Aniline (X = Cl, Br	#2 (R variation)
HBV-CSU-114	—	X = Cl	Br
HBV-CSU-115	Negishi coupling	X = Cl	Methyl
HBV-CSU-116	Suzuki coupling	X = Cl
HBV-CSU-117	Suzuki coupling	X = Cl
HBV-CSU-156	Suzuki coupling	X = Cl
HBV-CSU-157	Suzuki coupling	X = Cl
HBV-CSU-158	Suzuki coupling	X = Cl
HBV-CSU-159	Suzuki coupling	X = Cl
HBV-CSU-160	Stille coupling	X = Cl
HBV-CSU-161	Suzuki coupling	X = Cl
HBV-CSU-162	Suzuki coupling	X = Cl
HBV-CSU-163	Suzuki coupling	X = Cl
HBV-CSU-188	Displacement	X = Cl
HBV-CSU-257	—	X = Br	Br
HBV-CSU-271	Suzuki coupling	X = Cl
HBV-CSU-272	Stille coupling	X = Cl
HBV-CSU-291	Suzuki coupling	X = Cl
HBV-CSU-292	Suzuki coupling	X = Cl
HBV-CSU-293	Suzuki coupling	X = Cl
HBV-CSU-312	Suzuki coupling	X = Cl
HBV-CSU-313	Suzuki coupling	X = Cl
HBV-CSU-314	Suzuki coupling	X = Cl
HBV-CSU-321	Suzuki coupling	X = Cl

Synthesis of Methyl 4-(5-bromothiophen-2-yl)-2,4-dioxobutanoate (56)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 115 g (81%, reaction scale is 100 g) as a brown solid. TLC: 10% MeOH/DCM (R_f: 0.1); ¹H NMR (DMSO-d₆, 400 MHz): δ 8.12 (d, J=4.0 Hz, 1H), 7.45 (d, J=4.0 Hz, 1H), 7.03 (br.s, 1H), 3.84 (s, 3H); {Note: Enol form observed by ¹H NMR and peak for enolic alcohol was not observed}. LCMS Calculated for C₉H₇BrO₄S: 289.92; Observed: 290.95 (M+1)⁺.

Synthesis of Methyl 5-(5-bromothiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (57)

Title compound was synthesized using general method B for the synthesis of cyclic sulfonamide described above to afford 100 g (72%, reaction scale is 115 g) as a brown colored solid. TLC: 20% MeOH/DCM (R_f: 0.1); ¹H NMR (DMSO-d₆, 400 MHz): δ 7.85 (d, J=4.0 Hz, 1H), 7.33 (d, J=4.0 Hz, 1H), 6.87 (s 1H), 3.84 (s, 3H); LCMS Calculated for C₉H₇BrN₂O₄S₂: 349.90; LCMS observed: 352.90 (M+2)⁺.

Synthesis of Methyl 5-(5-bromothiophen-2-yl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (58)

Title compound was synthesized using general method A for alkylation described above to afford 65 g (62%, reaction scale is 100 g) as a brown solid. TLC: 40% EtOAc/hexanes (R_f: 0.4); ¹H NMR (DMSO-d₆, 400 MHz): δ 8.11 (d, J=4.0 Hz, 1H), 7.48 (d, J=4.0 Hz, 1H), 7.31 (s 1H), 3.93 (s, 3H), 3.50 (s, 3H); LCMS Calculated for C₁₀H₉BrN₂O₄S₂: 363.92; LCMS observed: 366.90 (M+2)⁺.

5-(5-Bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-0114-Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using Compound 58 and corresponding amine (see Table 1 for analytical data).

N-(3-Bromo-4-fluorophenyl)-5-(5-bromothiophen-2-yl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-257_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using Compound 58 and corresponding amine. The crude intermediate confirmed by LCMS and carried forward to the next step.

5-(5-Bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-114, HBV-CSU-114-ISO-I & HBV-CSU-114-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-0114-Int (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-methylthiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-115, HBV-CSU-115-ISO-I & HBV-CSU-115-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Negishi coupling by using HBV-CSU-114 and dimethyl zinc (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-phenylthiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-116-ISO-I & HBV-CSU-116-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-114 and corresponding boronic acid (see Table 2 for analytical data).

Cis-(5-benzylthiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-117, HBV-CSU-117-ISO-I & HBV-CSU-117-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-114 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(5-(4-cyano-3-fluorophenyl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-156, HBV-CSU-156-ISO-I & HBV-CSU-156-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-114 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(5-(4-bromo-3-fluorophenyl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-157)

The above titled compound has been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-114 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(6-(trifluoromethyl)pyridin-3-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-158, HBV-CSU-158-ISO-I & HBV-CSU-158-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-114 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(pyridin-3-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-159, HBV-CSU-159-ISO-I & HBV-CSU-159-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-114 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(pyridin-2-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-160, HBV-CSU-160-ISO-I & HBV-CSU-160-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-114 and corresponding stannane (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-161, HBV-CSU-161-ISO-I & HBV-CSU-161-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-114 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-5-([2,2′-bithiophen]-5-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-162, HBV-CSU-162-ISO-I & HBV-CSU-162-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-114 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(4-(methylsulfonamido)phenyl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-163, HBV-CSU-163-ISO-I & HBV-CSU-163-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-114 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(5-(2-(dimethylamino)ethoxy)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-188)

In a sealed tube, dimethyl amino ethanol (462 mg, 5.188 mmol) was taken in THF (10 mL), sodium metal (114.8 mg, 5.188 mmol) was added at 0° C. and stirred at room temperature for 30 min. To this reaction mixture, HBV-CSU-114 (500 mg, 1.0374 mmol) and CuBr (14.8 mg, 0.1037 mmol) were added and heated to 100° C. for overnight. The progress of reaction was monitored by TLC. After completion, the reaction mixture was quenched with saturated ammonium chloride and extracted with ethyl acetate. The combined organic layer was dried over anhydrous sodium sulphate, filtered and concerted under reduced pressure to afford the crude product which was purified by column chromatography to give of desired pure compound (12 mg, 2%) as a solid (see Table 2 for analytical data).

Cis-N-(3-Bromo-4-fluorophenyl)-5-(5-bromothiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-257)

The above titled compound has been synthesized by following the general procedure described above for reduction by using HBV-CSU-257-Int-1 (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-pyrazol-5-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-271, HBV-CSU-271-ISO-I & HBV-CSU-271-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-114 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(pyrimidin-5-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-272, HBV-CSU-272-ISO-I & HBV-CSU-272-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-114 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(5-(1-ethyl-1H-pyrazol-4-yl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-291, HBV-CSU-291-ISO-I & HBV-CSU-291-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-114 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(5-(1-isopropyl-1H-pyrazol-4-yl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-292, HBV-CSU-292-ISO-I & HBV-CSU-292-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-114 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(5-(1-(2-hydroxyethyl)-1H-pyrazol-4-yl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-293, HBV-CSU-293-ISO-I & HBV-CSU-293-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-114 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(5-(1,5-dimethyl-1H-pyrazol-4-yl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-312, HBV-CSU-312-ISO-I & HBV-CSU-312-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-114 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(5-(1,3-dimethyl-1H-pyrazol-4-yl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-313, HBV-CSU-313-ISO-I & HBV-CSU-313-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-114 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1,3,5-trimethyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-314-ISO-I & HBV-CSU-314-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-114 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(1-(trifluoromethyl)-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-321-ISO-I & HBV-CSU-321-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-114 and corresponding boronic acid (see Table 2 for analytical data).

Scheme 21:

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-phenyl-1,3,4-thiadiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-120, HBV-CSU-120-ISO-I & HBV-CSU-120-ISO-II)

Synthesis of Ethyl 5-bromo-1, 3, 4-thiadiazole-2-carboxylate (60)

To a stirred solution of compound 59 (21 g, 121.38 mmol) in ACN (400 mL), CuBr₂ (53.3 g, 239.01 mmol) was added and stirred at room temperature for 15 min. To this solution, tert-butyl nitrite (24.65 g, 239.04 mmol) was added drop wise over a period of 20 min. The resulting reaction mixture was stirred at room temperature for 30 min. and then heated at 60° C. for 30 min. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was diluted with water; ethyl acetate and filtered through Celite bed. The organic layer was separated; washed with brine; dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford the title compound 60 (25 g, 87.40%) as a yellow solid. TLC: 20% EtOAc/hexane (R_f: 0.7); ¹H NMR (400 MHz, DMSO-d₆): δ 4.45-4.40 (m, 2H), 1.34 (t, J=6.8 Hz, 3H).

Synthesis of (5-bromo-1, 3, 4-thiadiazol-2-yl)methanol (61)

To a stirred solution of compound 60 (25 g, 105.96 mmol) in MeOH (250 mL) at 0° C., NaBH₄ (12 g, 317.20 mmol) was added portion wise and stirred at room temperature for 16 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was quenched with acetic acid (5 mL); diluted with water and extracted with ethyl acetate. The combined organic layers were washed with sat. NaHCO₃ solution; dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain crude. The crude was purified through silica gel column chromatography using 15% EtOAc/hexanes to afford compound 61 (15 g, 73%) as yellow solid. TLC: 40% EtOAc/hexanes (R_f: 0.3); ¹H NMR (400 MHz, DMSO-d₆): δ 6.39 (t, J=6.0 Hz, 1H), 4.85-4.83 (s, 2H); LCMS Calculated for C₃H₃BrN₂OS: 193.91; Observed: 194.90 (M+1)⁺.

Synthesis of (5-phenyl-1, 3, 4-thiadiazol-2-yl)methanol (62)

To a mixture of bromo compound 61 (3 g, 15.54 mmol) and phenylboronic acid (2.27 g, 18.65 mmol) in toluene: EtOH (1:1, 160 mL) mixture, 2M Na₂CO₃ solution (4.92 g, 46.41 mmol) was added and purged with Ar for 30 min. To this solution, Pd(PPh₃)₄ (0.890 g, 0.77 mmol) was added and the reaction mixture was stirred at 100° C. for 3 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was filtered through Celite bed and filtrate was concentrated in vacuo. The residue was diluted with water and extracted with ethyl acetate. The combined organic layers were washed brine; dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain crude. The crude was purified through silica gel column chromatography using 15% EtOAc/hexanes to afford compound 62 as yellow solid. Same reaction was carried out on 2×3 g scale to afford 11 g of desired compound. TLC: 50% EtOAc/hexanes (R_f: 0.5); LCMS Calculated for C₉H₈N₂OS: 192.04; Observed: 192.95 (M+1)⁺.

Synthesis of 5-phenyl-1, 3, 4-thiadiazole-2-carbaldehyde (63)

To a stirred solution of compound 62 (11 g, 57.29 mmol) in DCM (330 mL), Dess-Martin periodinane (36.47 g, 85.98 mmol) was added. The resulting reaction mixture was stirred at room temperature for 3 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched by adding sat. NaHCO₃ solution; sat. sodium thiosulphate solution and extracted with ethyl acetate. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 5% EtOAc/hexanes to afford compound 63 (8 g, 73.5%) as an off white solid. TLC: 50% EtOAc/hexanes (R_f: 0.4); ¹H NMR (400 MHz, DMSO-d₆): δ 10.18 (s, 1H), 8.12-8.10 (m, 1H), 7.67-7.55 (m, 4H).

Synthesis of 1-(5-phenyl-1, 3, 4-thiadiazol-2-yl)ethan-1-ol (64)

To a stirred solution of compound 63 (8 g, 42.10 mmol) in dry THF (80 mL) at 0° C., under inert atmosphere, methyl magnesium iodide (3M, 42 mL, 126.70 mmol) was added dropwise. The resulting reaction mixture was stirred at room temperature for 2 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with saturated ammonium chloride solution and extracted with ethyl acetate. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 20% EtOAc/hexanes to afford compound 64 (0.5 g, 76.53%) as white solid. TLC: 40% EtOAc/hexanes (R_f: 0.2); ¹H NMR (400 MHz, DMSO-d₆): δ 7.97-7.95 (m, 2H), 7.56-7.54 (m, 3H), 6.41 (d, J=4.8 Hz, 1H), 5.15-5.12 (m, 1H), 1.50-1.40 (m, 3H); LCMS Calculated for C₁₀H₁₀N₂OS: 206.05; Observed: 206.90 (M+1)⁺.

Synthesis of 1-(5-phenyl-1, 3, 4-thiadiazol-2-yl)ethan-1-one (65)

To a stirred solution of compound 64 (7 g, 33.98 mmol) in DCM (70 mL), Dess-Martin periodinane (27.37 g, 64.56 mmol) was added. The resulting reaction mixture was stirred at room temperature for 3 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched by adding sat. NaHCO₃ solution; sat. sodium thiosulphate solution and extracted with ethyl acetate. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 5% EtOAc/hexanes to afford compound 65 (3.2 g, 43.24%) as an off white solid. TLC: 20% EtOAc/hexanes (R_f: 0.4); ¹H NMR (400 MHz, DMSO-d₆): δ 8.08-8.05 (m, 2H), 7.62-7.54 (m, 3H), 2.73 (m, 3H); LCMS Calculated for C₁₀H₈N₂OS: 204.04; Observed: 204.95 (M+1)⁺.

Synthesis of Methyl 2, 4-dioxo-4-(5-phenyl-1, 3, 4-thiadiazol-2-yl)butanoate (66)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 4.44 g (crude, reaction scale is 3.13 g) as a light brown solid. TLC: 40% EtOAc/hexanes (R_f: 0.1); LCMS Calculated for C₁₃H₁₀N₂O₄S: 290.04; Observed: 290.95 (M+1)⁺.

Synthesis of Methyl 5-(5-phenyl-1, 3, 4-thiadiazol-2-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (67)

Title compound was synthesized using general method B for the synthesis of cyclic sulfonamide described above to afford 1.2 g (24.89%, reaction scale is 4 g) as a light brown solid. ¹H NMR (DMSO-d₆, 400 MHz): δ 8.07-8.04 (m, 2H), 7.61-7.55 (m, 3H), 6.93 (s, 1H), 3.82 (s, 3H); LCMS Calculated for C₁₃H₁₀N₄O₄S₂: 350.01; LCMS observed: 351 (M+1)⁺.

Synthesis of Methyl 2-methyl-5-(5-phenyl-1, 3, 4-thiadiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (68)

Title compound was synthesized using general method B for alkylation described above to afford 1 g (96.15%, reaction scale is 1 g) as a light yellow solid. TLC: 40% EtOAc/hexanes (R_f: 0.3).

Synthesis of N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-phenyl-1,3,4-thiadiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-120_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using compound 68 and corresponding amine (see Table 1 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-phenyl-1, 3, 4-thiadiazol-2-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-120, HBV-CSU-120-ISO-I & HBV-CSU-120-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-120_Int (see Table 2 for analytical data).

Scheme 22:

General Synthetic Scheme for 5-(thiazol-2-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide Derivatives with 5-substituted Thiazole Variations

Target	Coupling reaction	#2 (R variation)
HBV-CSU-122	—	Br
HBV-CSU-124	Suzuki coupling
HBV-CSU-173	Suzuki coupling
HBV-CSU-175	Suzuki coupling
HBV-CSU-176	Stille coupling
HBV-CSU-177	Suzuki coupling
HBV-CSU-178	Suzuki coupling
HBV-CSU-179	Suzuki coupling
HBV-CSU-248	Suzuki coupling
HBV-CSU-250	Suzuki coupling
HBV-CSU-252	Stille coupling
HBV-CSU-254	Suzuki coupling
HBV-CSU-276	Stille coupling
HBV-CSU-277	Stille coupling
HBV-CSU-278	Stille coupling
HBV-CSU-280	Suzuki coupling
HBV-CSU-281	Suzuki coupling

Synthesis of 2-(2-methyl-1, 3-dioxolan-2-yl) thiazole (69)

To a stirred solution of 1-(thiazol-2-yl) ethan-1-one 9 (13 g, 102.36 mmol) in Toluene (250 mL) under inert atmosphere were added ethane-1, 2-diol (5.71 mL, 153.54 mmol) and p-toluene sulfonic acid (1.16 g, 6.14 mmol) at room temperature, followed by heating to 120° C. using a dean stark apparatus, and stirring for 24 h. The reaction was monitored by TLC. After completion, volatiles were removed in vacuo to obtain the crude. The crude was diluted with CH₂Cl₂ (300 mL) and washed with 10% NaHCO₃ solution (100 mL). The organic extract was dried over anhydrous sodium sulfate and concentrated in vacuo to afford compound 69 (13 g, 74%) as a yellow liquid. TLC: 10% EtOAc/hexanes (R_f: 0.5); ¹H NMR (DMSO-d₆, 400 MHz): δ 7.80 (d, J=3.1 Hz, 1H), 7.71 (d, J=3.2 Hz, 1H), 4.08-4.01 (m, 2H), 4.00-3.93 (m, 2H), 1.71 (s, 3H); LCMS Calculated for C₇H₉NO₂S: 171.04; Observed: 171.8 (M+1)⁺.

Synthesis of 5-bromo-2-(2-methyl-1, 3-dioxolan-2-yl) thiazole (70)

To a stirred solution of compound 69 (17 g, 99.41 mmol) in anhydrous THF (275 mL) under inert atmosphere was added n-butyl lithium (39.7 mL, 99.4 mmol) dropwise for 15 min at −78° C. and, followed by stirring for 1 h. To this was added carbon tetra bromide (33 g, 99.4 mmol) in anhydrous THF (75 mL) dropwise for 20 min at −78° C., followed by warming to 0° C. and stirring for 30 min. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with saturated ammonium chloride solution (50 mL) and extracted with EtOAc (3×500 mL). The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 3% EtOAc/hexanes to afford compound 70 (15 g, 60%) as brown liquid. TLC: 10% EtOAc/hexanes (R_f: 0.8); ¹H NMR (DMSO-d₆, 400 MHz): δ 7.88 (s, 1H), 4.07-4.01 (m, 2H), 4.00-3.93 (m, 2H), 1.68 (s, 3H); LCMS Calculated for C₇H₈BrNO₂S: 248.95; Observed: 249.8 (M+1)⁺.

Synthesis of 1-(5-bromothiazol-2-yl) ethan-1-one (71)

To a stirred solution of compound 70 (15 g, 60.24 mmol) in a mixture of CH₂Cl₂ (150 mL) and H₂O (5 mL) was added trifluoroacetic anhydride (150 mL, 10 V) at 0° C., followed by warming to room temperature and stirring for 36 h. The reaction was monitored by TLC. After completion of the reaction, the volatiles were removed in vacuo. The crude was diluted with CH₂Cl₂ (500 mL) then washed with 10% aqueous NaHCO₃ solution (150 mL). The organic extract was dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to obtain the crude compound 71 (10.5 g, 85%) as brown solid. TLC: 10% EtOAc/hexanes (R_f: 0.8); ¹H-NMR (DMSO-d₆, 400 MHz): δ 8.21 (s, 1H), 2.60 (s, 3H); LCMS Calculated for C₅H₄BrNOS: 204.92; Observed: 208.0 (M+2)⁺.

Synthesis of Methyl 4-(5-bromothiazol-2-yl)-2, 4-dioxobutanoate (72)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 7.5 g (50%, reaction scale is 10.5 g) as off-white solid. TLC: 5% MeOH/CH₂Cl₂ (R_f: 0.4); ¹H NMR (400 MHz, DMSO-d₆): δ 8.27 (s, 1H), 7.00 (br.s, 1H), 3.84 (s, 3H); LCMS Calculated for C₈H₆BrNO₄S: 290.92; Observed: 294.0 (M+2)⁺.

Synthesis of Methyl 5-(5-bromothiazol-2-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (73)

Title compound was synthesized using general method for the synthesis of cyclic sulfonamide described above to afford 4 g (44%, reaction scale is 7.5 g) as pale brown solid. TLC: 10% MeOH/CH₂Cl₂ (R_f: 0.3); ¹H NMR (400 MHz, DMSO-d₆): δ 8.02 (s, 1H), 6.77 (s, 1H), 3.79 (s, 3H); LCMS Calculated for C₈H₆BrN₃O₄S₂: 350.90; Observed: 349.8 (M−1)⁺.

Synthesis of Methyl 5-(5-bromothiazol-2-yl)-2-methyl-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (74)

Title compound was synthesized using general procedure for alkylation (Method A) described above to afford 2 g (48%, reaction scale is 4 g) as an off-white solid. TLC: 30% EtOAc/hexanes (R_f: 0.8); ¹H NMR (500 MHz, DMSO-d₆): δ 8.34 (s, 1H), 7.37 (s, 1H), 3.94 (s, 3H), 3.59 (s, 3H).

Synthesis of 5-(5-bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-2H-1, 2, 6-thiadiazine-3-carboxamide 1, 1-dioxide (HBV-CSU-122_Int/HBV-CSU-435)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using Compound 74 and corresponding amine (see Table 1 for analytical data).

Cis-5-(5-bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-122, HBV-CSU-122-ISO-I & HBV-CSU-122-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-222_Int/HBV-CSU-435 (see Table 2 for analytical data).

Cis-5-(5-Bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-124, HBV-CSU-124-I & HBV-CSU-124-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-122 and corresponding boronic acid (see Table 2 for analytical data).

Cis-5-(5-(4-Bromo-3-fluorophenyl)thiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-173, HBV-CSU-173-ISO-I & HBV-CSU-173-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-122 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(pyridin-3-yl)thiazol-2-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-175, HBV-CSU-175-ISO-I & HBV-CSU-175-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-122 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(pyridin-2-yl)thiazol-2-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-176, HBV-CSU-176-ISO-I & HBV-CSU-176-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-122 and corresponding stannane (see Table 2 for analytical data).

Note: Stannane reagent was synthesized as per following protocol:

To a stirred solution of 2-bromopyridine (1 g, 6.32 mmol) in anhydrous THF (10 mL) under inert atmosphere was added n-butyl lithium (4.2 mL, 6.32 mmol, 1.6 M solution in hexanes) at −78° C. followed by stirring for 1 h. To this was added tributyltin chloride (1.71 mL, 6.32 mmol) drop wise for 10 min at −78° C., which was then stirred at the same temperature for 2 h, then warmed to room temperature and stirred for 2 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with saturated ammonium chloride (30 mL) and extracted with EtOAc (3×50 mL). The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude stannane compound (2 g) as yellow syrup. The crude was carried forward for next step without further purification. TLC: 10% EtOAc/hexanes (R_f: 0.5).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiazol-2-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-177, HBV-CSU-177-ISO-I & HBV-CSU-177-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-122 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(thiophen-2-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-178, HBV-CSU-178-ISO-I & HBV-CSU-178-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-122 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(4-(methylsulfonamido)phenyl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-179, HBV-CSU-179-ISO-I & HBV-CSU-179-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-122 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(5-(4-fluorophenyl)thiazol-2-yl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-248, HBV-CSU-248-ISO-I & HBV-CSU-248-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-122 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(5-(4-methoxyphenyl)thiazol-2-yl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-250, HBV-CSU-250-ISO-I & HBV-CSU-250-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-122 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(5-(5-fluoropyridin-2-yl)thiazol-2-yl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-252, HBV-CSU-252-ISO-I & HBV-CSU-252-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-122 and corresponding stannane (see Table 2 for analytical data).

Note: Stannane reagent was synthesized as per following protocol:

To a stirred solution of 2-bromo-5-fluoropyridine (300 mg, 1.71 mmol) in anhydrous Toluene (10 mL) under inert atmosphere was added n-butyl lithium (1.28 mL, 2.05 mmol, 1.6 M solution in hexanes) at −78° C. and stirred for 1 h. To this was added tributyltin chloride (0.55 mL, 2.05 mmol) drop wise for 5 min at −78° C., which was then warmed to 0° C. and stirred for 1.5 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with saturated ammonium chloride (30 mL) and extracted with EtOAc (3×50 mL). The combined organic extracts were washed with water (75 mL), brine (75 mL), then dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to obtain the crude stannane compound (1 g) as a colorless liquid. The crude was carried forward for next step without further purification. TLC: 5% EtOAc/hexanes (R_f: 0.8)

Cis-5-(5-(1H-pyrazol-4-yl)thiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-254, HBV-CSU-254-ISO-I & HBV-CSU-254-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-122 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-276, HBV-CSU-276-ISO-I & HBV-CSU-276-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-122 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-5-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-277, HBV-CSU-277-ISO-I & HBV-CSU-277-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-122 and corresponding boronic acid (see Table 2 for analytical data).

Cis-5-([5,5′-Bithiazol]-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-278, HBV-CSU-278-ISO-I & HBV-CSU-278-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-122 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-pyrazol-3-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-280, HBV-CSU-280-ISO-I & HBV-CSU-280-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-122 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-pyrazol-5-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-281, HBV-CSU-281-ISO-I & HBV-CSU-281-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-122 and corresponding boronic acid (see Table 2 for analytical data).

Scheme 23:

Synthesis of Cis-5-(5-bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-123, HBV-CSU-123-ISO-I & HBV-CSU-123-ISO-II)

Synthesis of 1-(5-methylthiazol-2-yl) ethan-1-one (76)

To a stirred solution of 5-methylthiazole 75 (9 g, 90.90 mmol) in anhydrous THF (200 mL) under inert atmosphere was added n-butyl lithium (40 mL, 99.99 mmol) dropwise for 30 min at −78° C. To this was added N-methoxy-N-methylacetamide (11.24 mL, 109.1 mmol) dropwise for 20 min at −78° C., followed by warming to 0° C. and stirring for 16 min. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with saturated ammonium chloride solution and extracted using EtOAc. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 3% EtOAc/hexanes to afford compound 76 (12 g, 94%) as pale yellow liquid. TLC: 10% EtOAc/hexanes (R_f: 0.5); ¹H NMR (DMSO-d₆, 400 MHz): δ 7.83 (s, 1H), 2.58 (s, 3H), 2.54 (s, 3H).

Synthesis of Methyl 4-(5-methylthiazol-2-yl)-2, 4-dioxobutanoate (77)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 14 g (73%, reaction scale is 12 g) as yellow solid. TLC: 5% MeOH/CH₂O₂ (R_f: 0.2); ¹H NMR (400 MHz, DMSO-d₆): δ 7.86 (br.s, 1H), 6.99 (br.s, 1H), 3.82 (s, 3H), 2.56 (s, 3H); LCMS Calculated for C₉H₉NO₄S: 227.03; Observed: 228.1 (M+1)⁺.

Synthesis of Methyl 5-(5-methylthiazol-2-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (78)

Title compound was synthesized using general method A for the synthesis of cyclic sulfonamide described above to afford 1.9 g (38%, reaction scale is 4 g) as an off-white solid (1.9 g, 38%). TLC: 10% MeOH/CH₂Cl₂ (R_f: 0.1); ¹H NMR (400 MHz, DMSO-d₆): δ 7.66 (s, 1H), 6.85 (s, 1H), 6.07 (br.s, 1H), 3.79 (s, 3H), 2.50 (s, 3H); LCMS Calculated for C₉H₉N₃O₄S₂: 287.00; Observed: 288.1 (M+1)⁺.

Synthesis of Methyl 2-methyl-5-(5-methylthiazol-2-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (79)

Title compound was synthesized using general method A for alkylation described above to afford 250 mg (48%, reaction scale is 500 mg) as an off-white solid. TLC: 40% EtOAc/hexanes (R_f: 0.4); ¹H NMR (400 MHz, DMSO-d₆): δ 7.96 (s, 1H), 7.41 (s, 1H), 3.94 (s, 3H), 3.57 (s, 3H), 2.60 (s, 3H); LCMS Calculated for C₁₀H_nN₃O₄S₂: 301.02; Observed: 302.1 (M+1)⁺.

Synthesis of N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-methylthiazol-2-yl)-2H-1, 2, 6-thiadiazine-3-carboxamide 1, 1-dioxide (HBV-CSU-123_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding 79 and corresponding amine (see Table 1 for analytical data).

Cis-5-(5-Bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-123, HBV-CSU-123-ISO-I & HBV-CSU-123-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-123_Int (see Table 2 for analytical data).

Scheme 24:

General Synthetic Scheme for 5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide Derivatives with 4-substituted Thiophene & Aniline Variations

Target	Coupling reaction	Aniline (X = Cl/Br)	#2 (R variation)
HBV-CSU-146	—	X = Cl	Br
HBV-CSU-147	Negishi coupling	X = Cl	Methyl
HBV-CSU-148	Suzuki coupling	X = Cl
HBV-CSU-149	Suzuki coupling	X = Cl
HBV-CSU-164	Suzuki coupling	X = Cl
HBV-CSU-165	Suzuki coupling	X = Cl
HBV-CSU-166	Suzuki coupling	X = Cl
HBV-CSU-167	Suzuki coupling	X = Cl
HBV-CSU-168	Stille coupling	X = Cl
HBV-CSU-169	Suzuki coupling	X = Cl
HBV-CSU-170	Suzuki coupling	X = Cl
HBV-CSU-171	Suzuki coupling	X = Cl
HBV-CSU-243	Stille coupling	X = Cl
HBV-CSU-258	—	X = Br	Br
HBV-CSU-289	Suzuki coupling	X = Cl
HBV-CSU-290	Suzuki coupling	X = Cl
HBV-CSU-294	Suzuki coupling	X = Cl
HBV-CSU-295	Suzuki coupling	X = Cl
HBV-CSU-296	Suzuki coupling	X = Cl
HBV-CSU-315	Suzuki coupling	X = Cl
HBV-CSU-316	Suzuki coupling	X = Cl
HBV-CSU-317	Suzuki coupling	X = Cl
HBV-CSU-325	Suzuki coupling	X = Cl

Synthesis of Methyl 4-(4-bromothiophen-2-yl)-2,4-dioxobutanoate (81)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 30 g (84.57%, reaction scale is 25 g); LCMS Calculated for C₉H₇BrO₄S: 289.92; Observed: 292.80 (M+2)⁺.

Synthesis of Methyl 5-(4-bromothiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (82)

Title compound was synthesized using general method for the synthesis of cyclic sulfonamide described above to afford 15 g (41.60%, reaction scale is 30 g); LCMS Calculated for C₉H₇BrN₂O₄S₂: 349.90; LCMS observed: 353.05 (M+2)⁺.

Synthesis of Methyl 5-(4-bromothiophen-2-yl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (83)

Title compound was synthesized using general method B for alkylation described above to afford 9 g (57.58%, reaction scale is 5 g); LCMS Calculated for C₁₀H₉BrN₂O₄S₂: 363.92; LCMS observed: 367.10 (M+2)⁺.

5-(4-Bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-146_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using Compound 83 and corresponding amine (see Table 1 for analytical data).

N-(3-Bromo-4-fluorophenyl)-5-(4-bromothiophen-2-yl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-258_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using Compound 90 and corresponding amine. The crude intermediate confirmed by LCMS and carried forward to the next step.

5-(4-Bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-146, HBV-CSU-146-ISO-I & HBV-CSU-146-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-146_Int (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(4-methylthiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-147, HBV-CSU-147-ISO-I & HBV-CSU-147-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and dimethyl zinc (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(4-phenylthiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-148-ISO-I & HBV-CSU-148-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-(4-benzylthiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-149-ISO-I & HBV-CSU-149-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(4-(4-cyano-3-fluorophenyl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-164, HBV-CSU-164-ISO-I & HBV-CSU-164-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(4-(4-bromo-3-fluorophenyl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-165)

The above titled compound has been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(4-(6-(trifluoromethyl)pyridin-3-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-166, HBV-CSU-166-ISO-I & HBV-CSU-166-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(4-(pyridin-3-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-167-ISO-I & HBV-CSU-167-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(4-(pyridin-2-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-168, HBV-CSU-168-ISO-I & HBV-CSU-168-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(4-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-169-ISO-I & HBV-CSU-169-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-4-([2,2′-bithiophen]-5-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-170, HBV-CSU-170-ISO-I & HBV-CSU-170-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(4-(4-(methylsulfonamido)phenyl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-171)

The above titled compound has been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(4-(5-fluoropyridin-2-yl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-243, HBV-CSU-243-ISO-I & HBV-CSU-243-ISO-II)

The above titled compound has been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-Bromo-4-fluorophenyl)-5-(4-bromothiophen-2-yl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-258)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using HBV-CSU-258-Int-1 (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(4-(1-methyl-1H-pyrazol-5-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-289, HBV-CSU-289-ISO-I & HBV-CSU-289-ISO-II)

The above titled compound has been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(4-(pyrimidin-5-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-290, HBV-CSU-290-ISO-I & HBV-CSU-290-ISO-II)

The above titled compound has been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(4-(1-ethyl-1H-pyrazol-4-yl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-294, HBV-CSU-294-ISO-I & HBV-CSU-294-ISO-II)

The above titled compound has been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(4-(1-isopropyl-1H-pyrazol-4-yl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-295, HBV-CSU-295-ISO-I & HBV-CSU-295-ISO-II)

The above titled compound has been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(4-(1-(2-hydroxyethyl)-1H-pyrazol-4-yl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-296, HBV-CSU-296-ISO-I & HBV-CSU-296-ISO-II)

The above titled compound has been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(4-(1,5-dimethyl-1H-pyrazol-4-yl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-315, HBV-CSU-315-ISO-I & HBV-CSU-315-ISO-II)

The above titled compound has been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(4-(1,3-dimethyl-1H-pyrazol-4-yl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-316, HBV-CSU-316-ISO-I & HBV-CSU-316-ISO-II)

The above titled compound has been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(4-(1,3,5-trimethyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-317, HBV-CSU-317-ISO-I & HBV-CSU-317-ISO-II)

The above titled compound has been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(4-(1-(trifluoromethyl)-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-325-ISO-I & HBV-CSU-325-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-146 and corresponding boronic acid (see Table 2 for analytical data).

Scheme 25:

Synthesis of 5-(4-bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-150)

Synthesis of 1-(4-bromothiazol-2-yl) ethan-1-one (85)

To a stirring solution of 2, 4-dibromothiazole 84 (50 g, 205.82 mmol) in anhydrous THF (500 mL) under inert atmosphere was added n-butyllithium (193 mL, 308.74 mmol) dropwise for 30 min at −40° C. and stirred for 1 h at the same temperature. To this was added 1-morpholinoethan-1-one (32 g, 248 mmol) in anhydrous THF (100 mL) dropwise for 20 min at −40° C. and stirred for 3 h. The reaction was monitored by TLC; after completion of the reaction, the reaction mixture was quenched with saturated ammonium chloride solution and extracted using EtOAc. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 1-2% EtOAc/hexanes to afford compound 85 (14 g, 33%) as an off-white solid. TLC: 10% EtOAc/hexanes (R_f: 0.8); ¹H NMR (DMSO-d₆, 400 MHz): δ 8.33 (s, 1H), 2.62 (s, 3H); LCMS Calculated for C₅H₄BrNOS: 204.92; LCMS observed: 208.0 (M+2)⁺.

Synthesis of Methyl 4-(4-bromothiazol-2-yl)-2, 4-dioxobutanoate (86)

To a stirring solution of 1-(4-bromothiazol-2-yl) ethan-1-one 85 (10 g, 48.53 mmol) in anhydrous THF (200 mL) under inert atmosphere was added potassium tert-butoxide (122 mL, 121.94 mmol, 1 M sol. in THF) dropwise for 25 min at −78° C. and stirred at the same temperature for 1 h. To this was added dimethyl oxalate (8.6 g, 72.81 mmol) drop wise for 20 min at −78° C.; warmed to room temperature and stirred for 16 h. The reaction was monitored by TLC; after completion of the reaction, the pH of the reaction mixture was quenched with 1N aq. HCl and extracted using diethyl ether. The combined organic extracts were dried over anhydrous sodium sulfate and concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 1.5-2% MeOH/CH₂Cl₂ to afford compound 86 (2 g, 14%) as yellow solid. TLC: 70% EtOAc/hexanes (R_f: 0.4); ¹H-NMR (DMSO-d₆, 400 MHz): δ 8.33 (s, 1H), 2.62 (s, 3H); LCMS Calculated for C₈H₆BrNO₄S: 290.92; LCMS observed: 292.0 (M+1)⁺.

Synthesis of Methyl 5-(4-bromothiazol-2-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (87)

Title compound was synthesized using general method A for cyclisation described above to afford 800 mg (33%, reaction scale is 2 g) as a brown solid. TLC: 10% MeOH/DCM (R_f: 0.1); ¹H NMR (DMSO-d₆, 400 MHz): δ 7.99 (s, 1H), 6.78 (s, 1H), 3.80 (s, 3H); LCMS Calculated for C₈H₆BrN₃O₄S₂: 350.90; LCMS observed: 351.90 (M+1)⁺.

Synthesis of Methyl 5-(4-bromothiazol-2-yl)-2-methyl-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (88)

Title compound was synthesized using general method A for alkylation described above to afford 350 mg (42%, reaction scale is 800 mg) as an off-white solid. TLC: 10% MeOH/DCM (R_f: 0.4); ¹H NMR (DMSO-d₆, 400 MHz): δ 8.40 (s, 1H), 7.35 (s, 1H), 3.96 (s, 3H), 3.61 (s, 3H); LCMS Calculated for C₉H₈BrN₃O₄S₂: 364.91; LCMS observed: 368.0 (M+2)⁺.

Synthesis of 5-(4-bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-2H-1, 2, 6-thiadiazine-3-carboxamide 1, 1-dioxide (HBV-CSU-150_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding 88 and corresponding amine (see Table 1 for analytical data).

Cis-5-(4-Bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-150)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-0150_Int (see Table 2 for analytical data).

Scheme 26

Synthesis of Cis-N-(3-Chloro-4-fluorophenyl)-5-(4-hydroxyphenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-201) & N-(3-chloro-4-fluorophenyl)-5-(4-(3-(dimethylamino)propoxy)phenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-208, HBV-CSU-208-ISO-I & HBV-CSU-208-ISO-II)

Cis-N-(3-Chloro-4-fluorophenyl)-5-(4-hydroxyphenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-201)

To a stirred solution of compound HBV-CSU-200 (50 mg, 0.116 mmol) in DCM (2 mL) at −40° C., BBr₃ (0.025 mL, 0.233 mmol) was added and stirred at room temperature for 4 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was quenched with sat. NaHCO₃ solution and extracted with DCM. The combined organic layers were dried over anhydrous sodium sulphate and concentrated under reduced pressure. The crude compound was purified by silica gel column chromatography to afford the desired compound as HBV-CSU-201 (20 mg, 41.66%) as a white solid (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(4-(3-(dimethylamino)propoxy)phenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-208, HBV-CSU-208-ISO-I & HBV-CSU-208-ISO-II)

Title compound was synthesized using general method B for alkylation described above to afford 150 mg (35.62%, reaction scale is 350 mg) as an off white solid. TLC: 10% MeOH/DCM (R_f: 0.2) (see Table 2 for analytical data).

Scheme 27:

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-5-(3-hydroxyphenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-205) & N-(3-Chloro-4-fluorophenyl)-5-(3-(3-(dimethylamino)propoxy)phenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-209)

Cis-N-(3-chloro-4-fluorophenyl)-5-(3-hydroxyphenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-205)

To a stirred solution of compound HBV-CSU-204 (0.71 g, 1.66 mmol) in DCM (7 mL) at −40° C., BBr₃ (7 mL) was added and stirred at room temperature for 4 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was quenched with sat. NaHCO₃ solution and extracted with DCM. The combined organic layers were dried over anhydrous sodium sulphate and concentrated under reduced pressure. The crude compound was purified by silica gel column chromatography to afford the desired compound as HBV-CSU-205 (0.6 g, 89.15%) as a white solid. TLC: 50% EtOAc/hexanes (R_f: 0.3) (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(3-(3-(dimethylamino)propoxy)phenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-209)

Title compound was synthesized using general method B for alkylation described above (see Table 2 for analytical data).

Scheme 28:

Synthesis of N-(3-chloro-4-fluorophenyl)-5-(4-cyanophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-213) & 5-(4-Carbamoylphenyl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-214)

5-(4-Carbamoylphenyl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-213_Int)

To a mixture of bromo compound (200 mg, 0.423 mmol) in DMF, tetrakistriphenyl phosphine palladium (48.8 mg, 0.0423 mmol) was added and purged with Ar for 15 min. To this solution, ZnCN₂ (99.52 mg, 0.847 mmol) was added and purged with Ar for another 15 min. The resulting reaction mixture was then stirred at 80° C. for overnight. The progress of the reaction was monitored by TLC. After completion of the reaction, the reaction mixture was filtered through Celite and evaporated to dryness. The residue was taken in ethyl acetate, washed with water, brine, dried over anhydrous sodium sulfate and evaporated under reduced pressure. The crude product was purified by column chromatography to afford HBV-CSU-213_Int (100 mg, 56.5%) as an orange liquid. TLC: 40% EtOAc/hexane (R_f: 0.3) (see Table 1 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(4-cyanophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-213)

The above titled compound has been synthesized by following the general procedure described above for reduction by using HBV-CSU-213_Int (see Table 2 for analytical data).

Cis-5-(4-Carbamoylphenyl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-214, HBV-CSU-214-ISO-I & HBV-CSU-214-ISO-II)

To a stirred solution of compound HBV-CSU-213 (0.3 g, 0.709 mmol) in DMSO (15 mL) at 0° C.,

K₂CO₃ (0.196 g, 1.42 mmol) and H₂O₂ (30% in water 0.241 mL, 2.13 mmol) were added and stirred at room temperature for 2 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was quenched with ice cold water. The precipitated solid was collected by filtration; washed with water and dried under reduced pressure to afford the desired compound as HBV-CSU-214 (0.1 g, 32.15%) as a white solid. TLC: 5% MeOH/DCM (R_f: 0.4) (see Table 2 for analytical data).

Scheme 29:

Synthesis of 2-(4-(5-((3-Chloro-4-fluorophenyl)carbamoyl)-6-methyl-1,1-dioxido-1,2,6-thiadiazinan-3-yl)phenoxy)acetic Acid (HBV-CSU-216, HBV-CSU-216-ISO-I & HBV-CSU-216-ISO-II)

tert-Butyl 2-(4-(5-((3-chloro-4-fluorophenyl)carbamoyl)-6-methyl-1,1-dioxido-1,2,6-thiadiazinan-3-yl)phenoxy)acetate (89)

Title compound was synthesized using general method B for alkylation described above to afford 0.15 g (23.68%, reaction scale is 0.5 g); ¹H-NMR (DMSO-d₆, 400 MHz): δ 10.53 (s, 1H), 7.96-7.94 (m, 1H), 7.56-7.35 (m, 5H), 6.88 (d, J=8.8 Hz, 2H), 4.65 (s, 2H), 4.54-4.49 (m, 1H), 4.26-4.19 (m, 1H), 2.63 (s, 3H), 2.09-2.01 (m, 2H), 1.42 (s, 9H).

Cis-2-(4-(5-((3-Chloro-4-fluorophenyl) carbamoyl)-6-methyl-1,1-dioxido-1,2,6-thiadiazinan-3-yl)phenoxy)acetic Acid (HBV-CSU-216, HBV-CSU-216-ISO-I & HBV-CSU-216-ISO-II)

To a stirred solution of compound 89 (50 mg, 0.246 mmol) in DCM (5 mL) at 0° C., TFA (0.083 mL, 0.739 mmol) was added and stirred at room temperature for 2 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was concentrated and co-evaporated with DCM twice and the residue obtained was triturated with di-ethyl ether to afford the desired compound as HBV-CSU-216 (90 mg, 78%) as an off white solid. TLC: 40% EtOAc/hexanes (R_f: 0.3) (see Table 2 for analytical data).

Scheme 30:

Synthesis of Cis-4-(5-((3-Chloro-4-fluorophenyl)carbamoyl)-6-methyl-1,1-dioxido-1,2,6-thiadiazinan-3-yl)benzoic Acid (HBV-CSU-218, HBV-CSU-218-ISO-I & HBV-CSU-218-ISO-II) and Cis-methyl 4-(5-((3-chloro-4-fluorophenyl)carbamoyl)-6-methyl-1,1-dioxido-1,2,6-thiadiazinan-3-yl)benzoate (HBV-CSU-256)

Cis-methyl 4-(5-((3-chloro-4-fluorophenyl)carbamoyl)-6-methyl-1,1-dioxido-1,2,6-thiadiazinan-3-yl)benzoate (HBV-CSU-256)

To a stirred solution of compound HBV-CSU-202 (0.5 g, 1.04 mmol) in MeOH:ACN (4:1, 2.5 mL) mixture under Ar atmosphere in an autoclave, TEA (0.05 mL, 0.312 mmol) and dppf (0.058 g, 0.104 mmol) were added and purged with Ar for 30 min. To this solution, Pd(OAc)₂ (0.023 g, 0.104 mmol) was added and again purged with carbon monoxide. The resulting reaction mixture was heated in autoclave at 100° C. for 150 psi pressure for 6 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was filtered through a pad of celite and filtrate was concentrated in vacuo. The residue was diluted with water (100 mL) and extracted with ethyl acetate (2×100 mL). The combined organic layers were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 10% EtOAc/hexane to afford compound HBV-CSU-256 (0.03 g, 6.3%) as a white solid. TLC: 40% EtOAc/hexane (R_f: 0.3) (see Table 2 for analytical data).

Cis-4-(5-((3-Chloro-4-fluorophenyl)carbamoyl)-6-methyl-1,1-dioxido-1,2,6-thiadiazinan-3-yl)benzoic Acid (HBV-CSU-218, HBV-CSU-218-ISO-I & HBV-CSU-218-ISO-II)

To a stirred solution of HBV-CSU-256 (0.25 g, 0.549 mmol) in THF: H₂O (1:1, 10 mL) mixture, aqueous LiOH (0.23 g, 5.49 mmol) was added and stirred at room temperature for 4 h. The progress of the reaction was monitored by TLC. After completion, the volatiles were removed in vacuo. The residue was acidified with 1N HCl to pH˜3 and extracted with ethyl acetate. The combined organic layers were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford the desired compound HBV-CSU-218 (0.1 g, 41.49%) as a white solid. TLC: 40% EtOAc/hexane (R_f: 0.1) (see Table 2 for analytical data).

Scheme 31:

General Synthetic Scheme for 5-(thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide Derivatives with 5-substituted Thiophene Variations (Reverse Suzuki Approach)

Target	Coupling reaction	#2 (R variation)
HBV-CSU-219	—	—CF3
HBV-CSU-242	Suzuki coupling
HBV-CSU-266	Suzuki coupling
HBV-CSU-267	Suzuki coupling
HBV-CSU-268	Suzuki coupling
HBV-CSU-270	Suzuki coupling
HBV-CSU-322	Suzuki coupling
HBV-CSU-323	Suzuki coupling

Synthesis of N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (90)

To a mixture of bromo compound HBV-CSU-114 (2 g, 4.143 mmol) and Bis(pinacolato)diboron (2.63 g, 10.35 mmol) in 1,4-dioxane (20 mL), potassium acetate (2.03 g, 20.71 mmol) was added and purged with Ar for 15 min. To this solution, PdCl₂(dppf). CH₂Cl₂ (0.101 g, 0.124 mmol) was added and the reaction mixture was stirred at 90° C. for overnight. The progress of the reaction was monitored by TLC. After completion of the reaction, the reaction mixture was filtered through Celite, evaporated to dryness to afford the desired Boronate ester as crude product 90 (2.35 g, crude) and used as such for the next step without further purification. TLC: 40% EtOAc/hexanes (R_f: 0.2); LCMS Calculated for C₂₁H₂₆BClFN₃O₅S₂: 529.11; Observed: 447.95 (M+1)⁺ for boronic acid.

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(trifluoromethyl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-219, HBV-CSU-219-ISO-I & HBV-CSU-219-II)

To a stirred solution of compound 90 (0.25 g, 0.472 mmol) and NaSO₂CF₃ (0.221 g, 1.417 mmol) in MeOH:DCM:H₂O (1:1:0.8, 5.6 mL) mixture at 0° C., CuCl (0.046 g, 0.472 mmol) was added and stirred for 10 min. To this solution, TBHP (70% aq., 0.303 mL, 2.36 mmol) was added slowly. The resulting reaction mixture was stirred at room temperature for overnight. The reaction was monitored by TLC. After completion, the reaction mixture was concentrated under reduced pressure and the crude compound obtained was purified by silica gel column chromatography using 15% EtOAc/hexane to afford the title compound HBV-CSU-219 (0.08 g, 36.03%) as an off-white solid. TLC: 40% EtOAc/hexanes (R_f: 0.5); (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(5-(5-fluoropyridin-2-yl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-242 HBV-CSU-242-ISO-I & HBV-CSU-242-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using compound 90 and corresponding bromo compound (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-4-yl)thiophen-2-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-266, HBV-CSU-266-ISO-I & HBV-CSU-266-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using compound 90 and corresponding bromo compound (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-5-yl)thiophen-2-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-267, HBV-CSU-267-ISO-I & HBV-CSU-267-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using compound 90 and corresponding bromo compound (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(thiazol-5-yl)thiophen-2-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-268, HBV-CSU-268-ISO-I & HBV-CSU-268-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using compound 90 and corresponding bromo compound (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-pyrazol-3-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-270, HBV-CSU-270-ISO-I & HBV-CSU-270-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using compound 90 and corresponding bromo compound (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-1,2,4-triazol-3-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-322-ISO-I & HBV-CSU-322-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using compound 90 and corresponding bromo compound (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-1,2,4-triazol-5-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-323-ISO-I & HBV-CSU-323-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using compound 90 and corresponding bromo compound (see Table 2 for analytical data).

Scheme 32:

Synthesis of N-(3-chloro-4-fluorophenyl)-5-(3-chloro-4-hydroxyphenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-220) & N-(3-Chloro-4-fluorophenyl)-5-(3,5-dichloro-4-hydroxyphenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-260)

Cis-N-(3-chloro-4-fluorophenyl)-5-(3-chloro-4-hydroxyphenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-220)

To a stirred solution of compound HBV-CSU-201 (200 mg, 0.483 mmol) in acetonitrile at 0° C., NCS (65 mg, 0.483 mmol) was added and stirred at room temperature for 3 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was concentrated and the crude compound was purified by silica gel column chromatography to afford the desired compound as HBV-CSU-220 (150 mg, 69.4%) as a white solid (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(3,5-dichloro-4-hydroxyphenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-260)

To a stirred solution of compound HBV-CSU-201 (200 mg, 0.483 mmol) in acetonitrile at 0° C., NCS (77 mg, 0.579 mmol) was added and stirred at room temperature for 16 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was concentrated and the crude compound was purified by silica gel column chromatography to afford the desired compound as HBV-CSU-260 (80 mg, 34.33%) as a white solid (see Table 2 for analytical data).

Scheme 33:

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-5-(4-cyano-3-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-221, HBV-CSU-221-ISO-I & HBV-CSU-221-ISO-II)

N-(3-Chloro-4-fluorophenyl)-5-(4-cyano-3-fluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-221_Int)

To a mixture of bromo compound (0.5 g, 1.02 mmol) in DMF (5 mL), tetrakistriphenyl phosphine palladium (0.118 g, 0.102 mmol) was added and purged with Ar for 15 min. To this solution, ZnCN₂ (0.239 g, 2.04 mmol) was added and purged with Ar for another 15 min. The resulting reaction mixture was then stirred at 80° C. for overnight. The progress of the reaction was monitored by TLC. After completion of the reaction, the reaction mixture was filtered through Celite and evaporated to dryness. The residue was taken in ethyl acetate, washed with water, brine, then dried over anhydrous sodium sulfate and evaporated under reduced pressure. The crude product was purified by column chromatography to afford HBV-CSU-221_Int (0.3 g, 67.41%) as an orange liquid. TLC: 40% EtOAc/hexane (R_f: 0.3) (see Table 1 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-(4-cyano-3-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-221, HBV-CSU-221-ISO-I & HBV-CSU-221-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-221_Int (see Table 2 for analytical data).

Scheme 34:

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-5-cyclopentyl-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-222, HBV-CSU-222-ISO-I & HBV-CSU-222-ISO-II)

Synthesis of Methyl 4-cyclopentyl-2, 4-dioxobutanoate (92)

Title compound was synthesized using general method tor the synthesis of 2, 4-diketoester described above to afford 6 g (97%, reaction scale is 3.5 g); LCMS Calculated for C₁₀H₁₄O₄: 198.05; Observed: 198.95 (M+1)⁺.

Synthesis of Methyl 5-cyclopentyl-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (93)

Title compound was synthesized using general method for the synthesis of cyclic sulfonamide described above to afford 5 g (64%, reaction scale is 6 g); LCMS Calculated for C₁₀H₁₄N₂O₄S: 258.07; LCMS observed: 259 (M+1)⁺.

Synthesis of Methyl 5-cyclopentyl-2-methyl-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (94)

Title compound was synthesized using general procedure for alkylation (Method B) described above to afford 4.5 g (85%, reaction scale is 5 g); LCMS Calculated for C₁₁H₁₆N₂O₄S: 272.08; LCMS observed: 273 (M+1)⁺.

Synthesis of N-(3-chloro-4-fluorophenyl)-5-cyclopentyl-2-methyl-2H-1, 2, 6-thiadiazine-3-carboxamide 1, 1-dioxide (HBV-CSU-222_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding Compound 94 and corresponding amine (see Table 1 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-5-cyclopentyl-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-222, HBV-CSU-222-ISO-I & HBV-CSU-222-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-222_Int (see Table 2 for analytical data).

Scheme 35:

Synthetic Scheme for N-(3-chloro-4-fluorophenyl)-2-methyl-5-(2-methylthiazol-5-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-224, HBV-CSU-224-ISO-I & HBV-CSU-224-ISO-II)

Synthesis of Ethyl 2-chloro-3-oxopropanoate (96)

To a stirred solution of ethyl 2-chloroacetate 95 (5 g, 40.98 mmol) and ethyl formate (3.33 mL, 40.98 mmol) in diisopropyl ether (50 mL) under Ar atmosphere was added potassium tert-butoxide (45 mL, 45.08 mmol, 1 M sol. in THF) portion wise for 20 min at 0° C., followed by warming to room temperature and stirring for 24 h. The reaction was monitored by TLC. After completion of the reaction, the pH of the reaction mixture was adjusted to −6 using 6 N HCl and extracted using diethyl ether. The combined organic extracts were dried over anhydrous sodium sulfate and concentrated in vacuo to afford compound 96 (5.6 g, 91%) as thick syrup. TLC: 40% EtOAc/hexanes (R_f: 0.7); ¹H-NMR (DMSO-d₆, 400 MHz): δ 11.75 (br.s, 1H), 4.14 (q, J=7.0 Hz, 2H), 4.05 (s, 1H), 1.21 (t, J=7.1 Hz, 3H).

Synthesis of Ethyl 2-methylthiazole-5-carboxylate (97)

To a stirring solution of compound 96 (110 g, 733.33 mmol) in ethanol (1.2 L) under Ar atmosphere were added ethanethioamide (54.99 g, 733.33 mmol) and anhydrous magnesium sulfate (55 mg, 454.66 mmol) at room temperature, followed by heating to 80° C. for 16 h. The reaction was monitored by TLC. After completion of the reaction, the volatiles were removed in vacuo. The residue was diluted with water and extracted using EtOAc. The organic extract was dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 10% EtOAc/hexanes to afford compound 97 (41 g, 33%) as thick syrup. TLC: 20% EtOAc/hexanes (R_f: 0.3); ¹H NMR (400 MHz, DMSO-d₆): δ 8.26 (s, 1H), 4.29 (q, J=7.2 Hz, 2H), 2.71 (s, 3H), 1.29 (t, J=7.1 Hz, 3H); LCMS Calculated for C₇H₉NO₂S: 171.04; Observed: 172.1 (M+1)⁺.

Synthesis of 2-methylthiazole-5-carboxylic Acid (98)

To a stirred solution of compound 97 (41 g, 239.76 mmol) in THF: H₂O (7:1, 400 mL) was added lithium hydroxide monohydrate (29.49 g, 719.29 mmol) at room temperature and stirred for 16 h. The reaction was monitored by TLC. After completion of the reaction, the volatiles were removed in vacuo. The residue was diluted with water and acidified with 2 N HCl to pH˜2 and extracted using EtOAc. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford compound 98 (14 g, 41%) as an off-white solid. TLC: 20% EtOAc/hexanes (R_f: 0.1); ¹H NMR (DMSO-d₆, 400 MHz) δ 13.29 (br.s, 1H), 8.16 (s, 1H), 2.69 (s, 3H); LCMS Calculated for C₅H₅NO₂S: 143.00; Observed: 144.1 (M+1)⁺.

Synthesis of N-methoxy-N, 2-dimethylthiazole-5-carboxamide (99)

To a stirred solution compound 98 (19 g, 132.86 mmol) in DMF (300 mL) under inert atmosphere were added EDCI.HCl (38.06 g, 199.26 mmol), HOBt (26.9 g, 199.25 mmol) N, O-dimethylhydroxylamine hydrochloride (15.3 g, 158.54 mmol) and diisopropylethylamine (69.48 mL, 398.44 mmol) at 0° C., followed by warming to room temperature and stirred for 16 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was diluted with ice-cold water and extracted using EtOAc. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel flash column chromatography using 50% EtOAc/hexanes to afford compound 99 (13 g, 53%) as thick syrup. TLC: 10% MeOH/CH₂Cl₂ (R_f: 0.7); ¹H NMR (500 MHz, DMSO-d₆): δ 8.26 (s, 1H), 3.75 (s, 3H), 3.27 (s, 3H), 2.68 (s, 3H); LCMS Calculated for C₇H₁₀N₂O₂S: 186.05; Observed: 187.1 (M+1)⁺.

Synthesis of 1-(2-methylthiazol-5-yl) ethan-1-one (100)

To a stirring solution of compound 99 (13 g, 69.89 mmol) in dry diethyl ether (200 mL) under inert atmosphere was added methyl magnesium bromide (69.8 mL, 209.67 mmol, 3 M sol. in diethyl ether) dropwise for 25 min at −40° C., following by warming to room temperature and stirring for 16 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with saturated ammonium chloride solution at 0° C. and extracted using diethyl ether. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel flash column chromatography using 20% EtOAc/hexanes to afford compound 100 (5.62 g, 57%) as yellow solid. TLC: 20% EtOAc/hexanes (R_f: 0.3); ¹H NMR (400 MHz, DMSO-d₆): δ 8.45 (s, 1H), 2.71 (s, 3H), 2.54 (s, 3H); LCMS Calculated for C₆H₇NOS: 141.02; Observed: 142.0 (M+1)⁺.

Synthesis of Methyl 4-(2-methylthiazol-5-yl)-2, 4-dioxobutanoate (101)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 9.01 g (99%, reaction scale is 5.62 g) as off-white sticky solid. TLC: 5% MeOH/CH₂Cl₂ (R_f: 0.4); LCMS Calculated for C₉H₉NO₄S: 227.03; Observed: 228.1 (M+1)⁺.

Synthesis of Methyl 5-(2-methylthiazol-5-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (102)

Title compound was synthesized using general method A for the synthesis of cyclic sulfonamide described above to afford 1.2 g (crude reaction scale is 1.2 g) as a light brown solid. TLC: 20% MeOH/CH₂Cl₂ (R_f: 0.2); LCMS Calculated for C₁₃H₁₀N₄O₄S₂: 287.00; LCMS observed: 288.1 (M+1)⁺.

Synthesis of Methyl 2-methyl-5-(2-methylthiazol-5-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (103)

Title compound was synthesized using general method A for alkylation described above to afford 100 mg (8%, over two steps, reaction scale is 1 g) as yellow solid. TLC: 40% EtOAc/hexanes (R_f: 0.3); ¹H NMR (400 MHz, DMSO-d₆): δ 8.77 (s, 1H), 7.36 (s, 1H), 3.94 (s, 3H), 3.51 (s, 3H), 2.76 (s, 3H); LCMS Calculated for C₁₀H₁₁N₃O₄S₂: 301.02; Observed: 302.1 (M+1)⁺.

Synthesis of N-(3-chloro-4-fluorophenyl)-2-methyl-5-(2-methylthiazol-5-yl)-2H-1, 2, 6-thiadiazine-3-carboxamide 1, 1-dioxide (HBV-CSU-224_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding 103 and corresponding amine (see Table 1 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(2-methylthiazol-5-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-224, HBV-CSU-224-ISO-I & HBV-CSU-224-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-224_Int (see Table 2 for analytical data).

Scheme 36:

Synthetic Scheme for N-(3-chloro-4-fluorophenyl)-2-methyl-5-(2-methylthiazol-5-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-226)

Synthesis of 2-(trifluoromethyl) thiazole-5-carboxylic Acid (105)

To a stirred solution of ethyl 2-(trifluoromethyl) thiazole-5-carboxylate 104 (1 g, 4.44 mmol) in CH₃CN: H₂O (1:1, 20 mL) was added triethylamine (3.2 mL, 22.22 mml) at 0° C.; warmed to room temperature and stirred for 16 h. The reaction was monitored by TLC. After completion of the reaction, the volatiles were removed in vacuo and further dried by azeotropic distillation using toluene to afford compound 105 (900 mg, crude) as pale yellow solid. TLC: 50% EtOAc/hexanes (R_f: 0.1); ¹H NMR (DMSO-d₆, 400 MHz) δ 10.66 (br.s, 1H), 8.18 (s, 1H).

Synthesis of N-methoxy-N-methyl-2-(trifluoromethyl) thiazole-5-carboxamide (106)

To a stirred solution compound 105 (900 mg, crude) in DMF (15 mL) under inert atmosphere were added N, O-dimethylhydroxylamine hydrochloride (537 mg, 5.47 mmol), HATU (3.47 g, 9.13 mmol) and diisopropylethylamine (2.38 mL, 13.66 mmol) at 0° C., followed by warming to room temperature and stirring for 16 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was poured into ice-cold water and extracted using CH₂Cl₂. The combined organic extracts were washed with 2 N HCl, dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 20% EtOAc/hexanes to afford compound 106 (600 mg, 60% over 2 steps) as brown liquid. TLC: 30% EtOAc/hexanes (R_f: 0.7); ¹H NMR (500 MHz, DMSO-d₆): δ 8.67 (s, 1H), 3.83 (s, 3H), 3.34 (s, 3H); LCMS Calculated for C₇H₇F₃N₂O₂S: 240.02; Observed: 241.1 (M+1)⁺.

Synthesis of 1-(2-(trifluoromethyl) thiazol-5-yl)ethan-1-one (107)

To a stirred solution of compound 106 (1.05 g, 4.37 mmol) in anhydrous diethyl ether (20 mL) under inert atmosphere was added methyl magnesium bromide (3.7 mL, 10.93 mmol, 3 M sol. in diethyl ether) dropwise for 10 min at −40° C. and stirred at the same temperature for 3 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with ice-cold water at 0° C. and extracted using diethyl ether. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford compound 107 (450 mg, crude) as pale yellow solid. TLC: 30% EtOAc/hexanes (R_f: 0.9); ¹H NMR (400 MHz, DMSO-d₆): δ 8.89 (s, 1H), 2.67 (s, 3H).

Synthesis of Methyl 2, 4-dioxo-4-(2-(trifluoromethyl) thiazol-5-yl) butanoate (108)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 400 mg (36%, over 2 steps, reaction scale is 450 mg) as an off-white solid. TLC: 2% MeOH/CH₂Cl₂ (R_f: 0.4); ¹H NMR (400 MHz, DMSO-d₆): δ 9.13 (br.s, 1H), 7.07 (br.s, 1H), 3.86 (s, 3H); LCMS Calculated for C₉H₆F₃NO₄S: 281.00; Observed: 279.9 (M+1)⁺.

Synthesis of Methyl 5-(2-(trifluoromethyl) thiazol-5-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (109)

Title compound was synthesized using general method A for the synthesis of cyclic sulfonamide described above to afford 400 mg (83%, reaction scale is 400 mg) as an off-white solid. TLC: 6% MeOH/CH₂Cl₂ (R_f: 0.1); ¹H NMR (400 MHz, DMSO-d₆): δ 8.75 (s, ¹H), 8.39 (br.s, 1H), 6.71 (s, 1H), 3.80 (s, 3H).

Synthesis of Methyl 2-methyl-5-(2-(trifluoromethyl) thiazol-5-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (110)

Title compound was synthesized using general method A for alkylation described above to afford 340 mg (83%, reaction scale is 400 mg) as an off-white solid. TLC: 5% MeOH/CH₂Cl₂ (R_f: 0.6); ¹H NMR (400 MHz, DMSO-d₆): δ 9.19 (s, 1H), 7.49 (s, 1H), 3.97 (s, 3H), 3.58 (s, 3H).

Synthesis of N-(3-chloro-4-fluorophenyl)-2-methyl-5-(2-(trifluoromethyl) thiazol-5-yl)-2H-1, 2, 6-thiadiazine-3-carboxamide 1, 1-dioxide (HBV-CSU-226_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding 110 and corresponding amine (see Table 1 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(2-(trifluoromethyl) thiazol-5-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-226)

The above titled compound has been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-226_Int (see Table 2 for analytical data).

Scheme 37:

Synthesis of Cis-3-chloro-4-fluorophenyl)-2-methyl-5-(2-phenylthiazol-5-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-235, HBV-CSU-235-ISO-I & HBV-CSU-235-ISO-II)

Synthesis of Ethyl 2-phenylthiazole-5-carboxylate (111)

To a stirring solution of benzothioamide (25 g, 182.48 mmol) in toluene (250 mL) under inert atmosphere were added ethyl 2-chloro-3-oxopropanoate 96 (41.15 g, 274.34 mmol), anhydrous magnesium sulfate (65.85 g, 547.44 mmol) at room temperature and heated to 90° C. and stirred for 16 h. The reaction was monitored by TLC; after completion of the reaction, the reaction mixture was diluted with water and extracted with EtOAc. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 10% EtOAc/hexanes to afford compound 111 (15 g, 35%) as pale yellow solid. TLC: 20% EtOAc/hexanes (R_f: 0.8); ¹H NMR (400 MHz, DMSO-d₆): δ 8.49 (s, 1H), 8.04-8.01 (m, 2H), 7.58-7.51 (m, 3H), 4.34 (q, J=7.2 Hz, 2H), 1.32 (t, J=7.1 Hz, 3H); LCMS Calculated for C₁₂H₁₁NO₂S: 233.05; LCMS observed: 234.1 (M+1)⁺.

Synthesis of 2-phenylthiazole-5-carboxylic Acid (112)

To a stirring solution of compound 111 (1 g, 4.28 mmol) in THF: H₂O (1:1, 20 mL) was added lithium hydroxide monohydrate (515 mg, 21.45 mmol) at room temperature and stirred for 6 h. The reaction was monitored by TLC; after completion of the reaction, the volatiles were removed in vacuo and the pH of the aqueous layer was neutralized with 1 N aqueous HCl. The precipitated solid was filtered and dried in vacuo to afford compound 112 (600 mg, 68%) as pale yellow solid. TLC: 30% EtOAc/hexanes (R_f: 0.1); ¹H NMR (DMSO-d₆, 400 MHz) δ 7.93 (s, 1H), 7.92-7.88 (m, 2H), 7.51-7.43 (m, 3H); LCMS Calculated for C₁₀H₇NO₂S: 205.02; LCMS observed: 206.1 (M+1)⁺.

Synthesis of N-methoxy-N-methyl-2-phenylthiazole-5-carboxamide (113)

To a stirring solution of compound 112 (10 g, 48.72 mmol) in DMF (150 mL) under inert atmosphere were added N, O-dimethylhydroxylamine hydrochloride (5.73 g, 58.46 mmol), EDCI.HCl (14 g, 73.17 mmol), HOBt (6.68 g, 48.787 mmol), N, N-diisopropylethylamine (25.5 mL, 146.73 mmol) at 0° C.; warmed to room temperature and stirred for 16 h. The reaction was monitored by TLC; after completion of the reaction, the reaction mixture was diluted with ice-cold water (500 mL) and extracted using EtOAc. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel flash column chromatography using 20% EtOAc/hexanes to afford compound 113 (9.6 g, 79%) as pale yellow liquid. TLC: 30% EtOAc/hexanes (R_f: 0.8); ¹H NMR (500 MHz, DMSO-d₆): δ 8.50 (s, 1H), 8.07-7.99 (m, 2H), 7.57-7.53 (m, 3H), 3.82 (s, 3H), 3.32 (s, 3H); LCMS Calculated for C₁₂H₁₂N₂O₂S: 248.06; LCMS observed: 249.1 (M+1)⁺.

Synthesis of 1-(2-phenylthiazol-5-yl) ethan-1-one (114)

To a stirring solution of compound 113 (1 g, 4.03 mmol) in anhydrous diethyl ether (10 mL) under inert atmosphere was added methyl magnesium bromide (3.36 mL, 10.08 mmol, 3 M sol. in diethyl ether) dropwise for 10 min at −40° C.; warmed to room temperature and stirred for 3 h. The reaction was monitored by TLC; after completion of the reaction, the reaction mixture was quenched with saturated ammonium chloride solution (50 mL) at 0° C. and extracted using EtOAc. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel flash column chromatography using 20% EtOAc/hexanes to afford compound 114 (600 mg, 74%) as pale yellow liquid. TLC: 20% EtOAc/hexanes (R_f: 0.7); ¹H NMR (500 MHz, DMSO-d₆): δ 8.70 (s, 1H), 8.04 (dd, J=7.8, 1.4 Hz, 2H), 7.61-7.52 (m, 3H), 2.61 (s, 3H); LCMS Calculated for C_HH₉NOS: 203.04; LCMS observed: 204.1 (M+1)⁺.

Synthesis of Methyl 2, 4-dioxo-4-(2-phenylthiazol-5-yl) butanoate (115)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 6.6 g (86%, reaction scale is 5.4 g) as a yellow colored solid. TLC: 5% MeOH/DCM (R_f: 0.6); ¹H NMR (DMSO-d₆, 400 MHz): δ 0.92 (br.s, 1H), 8.04-7.98 (m, 2H), 7.57-7.47 (m, 3H), 7.05 (br.s, 1H), 3.80 (s, 3H); LCMS Calculated for C₁₄H₁₁NO₄S: 289.04; LCMS observed: 290.1 (M+1)⁺.

Synthesis of Methyl 5-(2-phenylthiazol-5-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (116)

Title compound was synthesized using general method A for cyclisation described above to afford 3.2 g (41%, reaction scale is 6.5 g) as a pale yellow solid. TLC: 5% MeOH/DCM (R_f: 0.1); ¹H NMR (DMSO-d₆, 400 MHz): δ 8.66 (s, 1H), 8.03 (dd, J=6.4, 2.9 Hz, 2H), 7.58-7.50 (m, 3H), 6.85 (br.s, 1H), 3.84 (s, 3H); LCMS Calculated for C₁₄H_iiN₃O₄S₂: 349.02; LCMS observed: 350.1 (M+1)⁺.

Synthesis of Methyl 2-methyl-5-(2-phenylthiazol-5-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (117)

Title compound was synthesized using general method A for alkylation described above to afford 1.6 g (48% yield, reaction scale was 3.2 g) as an off-white solid. TLC: 30% EtOAc/hexanes (R_f: 0.8); ¹H NMR (DMSO-d₆, 400 MHz): δ 9.01 (s, 1H), 8.09 (d, J=6.7 Hz, 2H), 7.64-7.54 (m, 3H), 7.44 (s, 1H), 3.96 (s, 3H), 3.54 (s, 3H); LCMS Calculated for C₁₅H₁₃N₃O₄S₂: 363.03; LCMS observed: 364.1 (M+1)⁺.

Synthesis of N-(3-chloro-4-fluorophenyl)-2-methyl-5-(2-phenylthiazol-5-yl)-2H-1, 2, 6-thiadiazine-3-carboxamide 1, 1-dioxide (HBV-CSU-235_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding 117 and corresponding amine (see Table 1 for analytical data).

N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(2-phenylthiazol-5-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-235, HBV-CSU-235-ISO-I & HBV-CSU-235-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-235_Int (see Table 2 for analytical data).

Scheme 38:

Synthesis of Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(4-(1-methyl-1H-pyrazol-4-yl)phenyl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-246, HBV-CSU-246-ISO-I & HBV-CSU-246-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-202 and corresponding boronic acid (see Table 2 for analytical data).

Scheme 39:

Synthesis of N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(3-(1-methyl-1H-pyrazol-4-yl)phenyl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-247, HBV-CSU-247-ISO-I, HBV-CSU-247-ISO-II)

3-(5-((3-Chloro-4-fluorophenyl) carbamoyl)-6-methyl-1,1-dioxido-1,2,6-thiadiazinan-3-yl)phenyl trifluoromethanesulfonate (118)

To a stirred solution of compound HBV-CSU-205 (0.4 g, 0.968 mmol) in DCM at 0° C., pyridine (0.153 g, 1.93 mmol) was added drop wise and stirred at same temperature for 10 minutes. To this solution, triflic anhydride (0.327 mL 1.93 mmol) was added drop wise at 0° C. The resulting reaction mixture was stirred at room temperature for 4 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mass was concentrated under reduced pressure. The residue was quenched with 10% dil. HCl, washed with sat. NaHCO₃, brine, and dried in vacuo. The crude compound was purified by silica gel column chromatography to afford the desired compound 118 (0.17 g, 32.25%) as a white solid TLC: 40% EtOAc/hexanes (R_f: 0.4)

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(3-(1-methyl-1H-pyrazol-4-yl)phenyl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-247, HBV-CSU-247-ISO-I, HBV-CSU-247-ISO-II)

The above titled compound has been synthesized by following the general procedure described above for Suzuki coupling by using compound 118 and corresponding boronic acid (see Table 2 for analytical data).

Scheme 40:

Synthesis of N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(oxazol-5-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-269, HBV-CSU-269-ISO-I & HBV-CSU-269-II)

Synthesis of 5-(5-bromothiophen-2-yl)oxazole (120)

To a stirred solution of compound 119 (10 g, 52.36 mmol) and TosMIC (11.24 g, 57.59 mmol) in MeOH (300 mL), K₂CO₃ (7.91 g, 57.59 mmol) was added and reaction mixture was refluxed for 4 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 12% EtOAc/hexane to afford the title compound 120 (8.23 g, 62.50%) as a light yellow solid. TLC: 20% EtOAc/hexane (R_f: 0.3); ¹H NMR (DMSO-d₆, 400 MHz): δ 8.42 (s, 1H), 7.54 (s, 1H), 7.31-7.28 (m, 2H); LCMS Calculated for C₇H₄BrNOS: 228.92: Observed: 229.75 (M+1)⁺.

Synthesis of 1-(5-(oxazol-5-yl)thiophen-2-yl)ethan-1-one (122)

To a stirred solution of bromo compound 120 (7.6 g, 33.18 mmol) in toluene (150 mL), tributyl(1-ethoxyvinyl)stannane (17.97 g, 49.78 mmol) was added and purged with Ar for 15 min. To this solution, Pd(PPh₃)₂Cl₂ (1.16 g, 1.16 mmol) was added and the reaction mixture was stirred at 100° C. for overnight. The progress of the reaction was monitored by TLC. After completion, the intermediate compound 121 was treated with 2M HCl (60 mL) at reflux temperature for 3 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was concentrated in vacuo to obtain the crude which was purified through silica gel column chromatography using 15% EtOAc/hexane to afford the title compound 122 (4.75 g, 74.45%) as a light yellow solid. TLC: 30% EtOAc/hexane (R_f: 0.2) ¹H NMR (DMSO-d₆, 400 MHz): δ 8.52 (s, 1H), 7.97 (d, J=3.6 HZ, 1H), 7.78 (s, 1H), 7.59 (d, J=4.0 HZ, 1H), 2.56 (s, 3H); LCMS Calculated for C₉H₇NO₂S: 193.02: Observed: 194 (M+1)⁺.

Synthesis of Methyl 4-(5-(oxazol-5-yl)thiophen-2-yl)-2, 4-dioxobutanoate (123)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 5.5 g (84%, reaction scale is 4.5 g) as a yellow solid. 30% EtOAc/hexane (R_f: 0.1); LCMS Calculated for C₁₂H₉NO₅S: 279.02; Observed: 280 (M+1)⁺

Synthesis of Methyl 5-(5-(oxazol-5-yl)thiophen-2-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1,1-dioxide (124)

Title compound was synthesized using general method B for the synthesis of cyclic sulfonamide described above to afford 4 g (59.90%, reaction scale is 5.5 g) as brown solid. TLC: 5% MeOH/DCM (R_f: 0.1); ¹H NMR (DMSO-d₆, 400 MHz): δ 8.49 (s, 1H), 7.94 (d, J=4.0 Hz, 1H), 7.70 (s, 1H), 7.52 (d, J=4.0 Hz, 1H), 6.80 (s, 1H), 3.83 (s, 3H); LCMS Calculated for C₁₂H₉N₃O₅S₂: 339.00; LCMS observed: 340.05 (M+1)⁺.

Synthesis of Methyl 2-methyl-5-(5-(oxazol-5-yl)thiophen-2-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (125)

Title compound was synthesized using general method B for alkylation described above to afford 2.3 g (49.14%, reaction scale is 4.5 g) as a light brown solid. TLC: 10% MeOH/DCM (R_f: 0.1); ¹H NMR (DMSO-d₆, 400 MHz): δ 8.57 (s, 1H), 8.31 (d, J=4.0 Hz, 1H), 7.85 (s, 1H), 7.67 (d, J=4.4 Hz, 1H), 7.36 (s 1H), 3.94 (s, 3H), 3.51 (s, 3H); LCMS Calculated for C₁₃H₁₁N₃O₅S₂: 353.01; LCMS observed: 354.02 (M+1)⁺.

Synthesis of N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(oxazol-5-yl)thiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-269_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 125 and corresponding amine (see Table 1 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(oxazol-5-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-269, HBV-CSU-269-ISO-I & HBV-CSU-269-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-269_Int (see Table 2 for analytical data).

Scheme 41:

Synthesis of Cis-5-(benzo[d]thiazol-6-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-273)

Synthesis of 6-bromobenzo[d]thiazole (127)

Titled compound was prepared using the reported method in Organic Letters, 9(18), 3623-3625; 2007.

Synthesis of 6-bromobenzo[d]thiazole (128)

To a mixture of bromo compound 127 (7 g, 32.17 mmol) in toluene (70 mL), tributyl(1-ethoxyvinyl)stannane (11.40 g, 35.98 mmol) was added, purged with Ar for 15 min followed by the addition of PdCl₂ (PPh₃)₂ (2.29 g, 3.27 mmol) and then the resulting reaction mixture was stirred at 90° C. for overnight. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was concentrated in vacuo, the residue obtained was treated with 6N HCl at room temperature for 1 h. After completion, the reaction mixture was concentrated in vacuo, neutralized with aq. NaHCO₃ solution, extracted with ethyl acetate. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford compound 128 (4 g, 69%) as an off-white solid. TLC: 20% EtOAc/hexanes (R_f: 0.2); ¹H NMR (DMSO-d₆, 400 MHz): δ 9.18 (s, 1H), 8.62 (s, 1H), 8.20 (d, J=8.8 Hz, 1H), 8.12 (d, J=8.8 Hz, 1H), 2.72 (s, 3H); LCMS Calculated for C₉H₇NOS: 177.02; LCMS observed: 178 (M+1)⁺.

Synthesis of Methyl 4-(benzo[d]thiazol-6-yl)-2,4-dioxobutanoate (129)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 5 g of Compound 129 (84%, reaction scale is 4 g) as a brown solid. TLC: 40% EtOAc/hexanes (R_f: 0.2).

Synthesis of Methyl 5-(benzo[d]thiazol-6-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (130)

Title compound was synthesized using general method A for cyclisation described above to afford 0.5 g of Compound 130 (10%, reaction scale is 4 g) as a brown solid. TLC: 20% MeOH/DCM (R_f: 0.1); ¹H NMR (DMSO-d₆, 400 MHz): δ 9.51 (s, 1H), 8.83 (s, 1H), 8.16-8.06 (m, 2H), 6.88 (s, 1H), 3.84 (s, 3H); LCMS Calculated for C₁₂H₉N₃O₄S₂: 323.00; LCMS observed: 324 (M+1)⁺.

Synthesis of Methyl 5-(benzo[d]thiazol-6-yl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (131)

Title compound was synthesized using general method B for alkylation described above to afford 0.4 g of Compound 131 (76% yield, reaction scale was 0.5 g) as a brown solid. TLC: 40% EtOAc/hexanes (R_f: 0.3); ¹H NMR (CDCl3, 400 MHz): δ 9.20 (s, 1H), 8.75 (s, 1H), 8.25 (d, J=8.8 Hz, 1H), 8.16 (d, J=8.8 Hz, 1H), 7.25 (s, 1H), 4.04 (s, 3H), 3.72 (s, 3H); LCMS Calculated for C₁₃H₁₁N₃O₄S₂: 337.02; LCMS observed: 338 (M+1)⁺.

Synthesis of 5-(benzo[d]thiazol-6-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-273_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding 131 and corresponding amine (see Table 1 for analytical data).

Synthesis of Cis-5-(benzo[d]thiazol-6-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-273)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-273_Int (see Table 2 for analytical data).

Scheme 42:

General Synthetic Scheme for 5-(thiophen-2-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide Derivatives with 4-substituted Thiophene

Target R variation
HBV-CSU-284
HBV-CSU-285
HBV-CSU-286
HBV-CSU-288
HBV-CSU-326
HBV-CSU-327

Synthesis of N-(3-chloro-4-fluorophenyl)-2-methyl-5-(4-(4, 4, 5, 5-tetramethyl-1, 3, 2-dioxaborolan-2-yl)thiophen-2-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (132)

To a mixture of bromo compound HBV-CSU-146 (3 g, 6.21 mmol) and Bis(pinacolato)diboron (3.95 g, 15.53 mmol) in 1,4-dioxane (30 mL), potassium acetate (3.04 g, 31.05 mmol) was added and purged with Ar for 15 min. To this solution, 1,1′-Bis(diphenylphosphino) ferrocene palladium(II)dichloride dichloromethane adduct (PdCl₂(dppf). CH₂Cl₂) (0.152 g, 0.186 mmol) was added and the reaction mixture was stirred at 90° C. for overnight. The progress of the reaction was monitored by TLC. After completion of the reaction, the reaction mixture was filtered through Celite, evaporated to dryness to afford the desired Boronate ester as crude product 132 (2.35 g, crude) and used as such for the next step without further purification. TLC: 40% EtOAc/hexanes (R_f: 0.2); LCMS Calculated for C₂₁H₂₆BClFN₃O₅S₂: 529.11; Observed: 448.05 (M+1)⁺ for boronic acid.

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-284, HBV-CSU-284-ISO-I & HBV-CSU-284-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using compound 132 and corresponding bromo compound (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(4-(1-methyl-1H-imidazol-5-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-285, HBV-CSU-285-ISO-I & HBV-CSU-285-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using compound 132 and corresponding bromo compound (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(4-(thiazol-5-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-286, HBV-CSU-286-ISO-I & HBV-CSU-286-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using compound 132 and corresponding bromo compound (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(4-(1-methyl-1H-pyrazol-3-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-288, HBV-CSU-288-ISO-I & HBV-CSU-288-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using compound 132 and corresponding bromo compound (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(4-(1-methyl-1H-1,2,4-triazol-3-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-326-ISO-I & HBV-CSU-326-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using compound 132 and corresponding bromo compound (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(4-(1-methyl-1H-1,2,4-triazol-5-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-327-ISO-I & HBV-CSU-327-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using compound 132 and corresponding bromo compound (see Table 2 for analytical data).

Scheme 43:

Synthesis of N-(3-chloro-4-fluorophenyl)-2-methyl-5-(4-methyl-5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-300, HBV-CSU-300-ISO-I & HBV-CSU-300-ISO-I) and 5-(5-bromo-4-methylthiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-335)

Synthesis of 1-(5-bromo-4-methylthiophen-2-yl) ethan-1-one (134)

To a stirred solution of compound 133 (10 g, 56.49 mmol) in DCM (100 mL) at 0° C., AlCl₃ (9.3 g, 70.62 mmol) was added and stirred for 10 min. To this solution, acetyl chloride (4.85 g, 61.51 mmol) was added at the same temperature and the resulting reaction mixture was stirred at room temperature for 16 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was cooled to 0° C.; quenched by adding ice cold water, basified using sat. NaHCO₃ solution and then extracted using DCM. The combined organic layers were collected, dried over anhydrous sodium sulphate, filtered and concentrated in vacuo to afford the crude compound. The crude compound was purified by silica gel column chromatography using 5% EtOAc/hexane to afford the title compound 134 (12 g, 97%) as a brown solid. TLC: 10% EtOAc/hexane (R_f: 0.4); LCMS Calculated for C₇H₇BrOS: 217.94; Observed: 218.80 (M)⁺.

Synthesis of Methyl 4-(5-bromo-4-methylthiophen-2-yl)-2,4-dioxobutanoate (135)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 15 g (90.09%, reaction scale is 12 g) as a brown solid. TLC: 20% EtOAc/hexane (R_f: 0.1). The crude material was used as such in the next reaction without further characterization.

Synthesis Methyl 5-(5-bromo-4-methylthiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (136)

Title compound was synthesized using general method B for the synthesis of cyclic sulfonamide described above to afford 13 g of compound 136 (72.22%, reaction scale is 15 g) as yellow solid. TLC: 50% EtOAc/hexane (R_f: 0.1); LCMS Calculated for C₁₀H₉BrN₂O₄S₂: 363.92; LCMS observed: 366.90 (M+2)⁺.

Synthesis of Methyl 5-(5-bromo-4-methylthiophen-2-yl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (137)

Title compound was synthesized using general method B for alkylation described above to afford 10 g of compound 137 (75%, reaction scale is 13 g) as a yellow solid. TLC: 40% EtOAc/hexanes (R_f: 0.3); LCMS Calculated for C₁₁H_nBrIN₂O₄S₂:377.93; LCMS observed: 381.25 (M+2)⁺.

Synthesis of 5-(5-bromo-4-methylthiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-335_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using compound 137 and corresponding amine (see Table 1 for analytical data).

Cis-5-(5-bromo-4-methylthiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-335)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-335_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(4-methyl-5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-300, HBV-CSU-300-ISO-I & HBV-CSU-300-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-335 and corresponding bromo compound (see Table 2 for analytical data).

Scheme 44:

Synthesis of N-(3-chloro-4-fluorophenyl)-5-(4-chloro-5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-302, HBV-CSU-302-ISO-I & HBV-CSU-302-ISO-II)

Synthesis of 2-bromo-3-chlorothiophene (139)

To a stirred solution of compound 138 (5 g, 42.37 mmol) in CCl₄ (30 mL) at 0° C., Br₂ (6.4 g, 40.25 mmol) was added drop wise. The resulting reaction mixture was stirred room temperature for 12 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was cooled to 0° C.; quenched by adding aq. Sodium thiosulphate and 50% NaOH solution and extracted with DCM. The combined organic layers were collected, dried over anhydrous sodium sulphate and concentrated in vacuo to afford the title compound 139 (6 g, 71.94%) as a colorless liquid and used as such for the next step without further purification TLC: hexane (R_f: 0.4); ¹H NMR (DMSO-d₆, 400 MHz): δ 7.75 (d, J=5.6 Hz, 1H), 7.11 (d, J=6.0 Hz, 1H).

Synthesis of 1-(5-bromo-4-chlorothiophen-2-yl)ethan-1-one (140)

To a stirred solution of compound 139 (6 g, 30.45 mmol) in DCM (300 mL) at 0° C., AlCl₃ (4.41 g, 33.16 mmol) was added and stirred for 10 min. To this solution, acetyl chloride (2.96 g, 38.07 mmol) was added at same temperature. The resulting reaction mixture was stirred room temperature for 16 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was cooled to 0° C.; quenched by adding ice cold water; sat. NaHCO₃ solution and extracted using DCM. The combined organic layers were collected, dried over anhydrous sodium sulphate, filtered and concentrated in vacuo to afford the crude. The crude was purified by silica gel column chromatography using 10% EtOAc/hexane to afford the title compound 140 (5.5 g, 75.34%) as a brown solid TLC: 5% EtOAc/hexane (R_f: 0.3)¹H NMR (DMSO-d₆, 400 MHz): δ 8.06 (s, 1H), 2.52 (s, 3H). LCMS Calculated for C₆H₄BrClOS: 237.89; Observed: 240.85 (M+2)⁺.

Synthesis of Methyl 4-(5-bromo-4-chlorothiophen-2-yl)-2,4-dioxobutanoate (141)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 10 g of compound 141 (crude, reaction scale is 5.5 g) as a brown solid TLC: 10% MeOH/DCM (R_f: 0.1). The crude material was used as such in the next reaction without further characterization.

Synthesis Methyl 5-(5-bromo-4-chlorothiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (142)

Title compound was synthesized using general method B for the synthesis of cyclic sulfonamide described above to afford 7 g of compound 142 (58%, reaction scale is 10 g) as yellow solid. TLC: 20% EtOAc/hexane (R_f: 0.1); ¹H NMR (DMSO-d₆, 400 MHz): δ 7.96 (s, 1H), 6.72 (s, 1H), 3.81 (s, 3H); LCMS Calculated for C₉H₆BrClN₂O₄S₂: 383.86; LCMS observed: 386.90 (M+2)⁺.

Synthesis of Methyl 5-(5-bromo-4-chlorothiophen-2-yl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (143)

Title compound was synthesized using general method B for alkylation described above to afford 9 g of compound 143 (crude, reaction scale is 7 g) as a yellow solid. TLC: 40% EtOAc/hexanes (R_f: 0.4); ¹H NMR (DMSO-d₆, 400 MHz): δ 8.41 (s 1H), 7.37 (s, 1H), 3.94 (s, 3H), 3.53 (s, 3H); LCMS Calculated for C₁₀H₈BrClN₂O₄S₂: 397.88; LCMS observed: 401.25 (M+2)⁺.

Synthesis of 5-(5-bromo-4-chlorothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1, 1-dioxide (HBV-CSU-329_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using compound 143 and corresponding amine (see Table 1 for analytical data).

Cis-5-(5-bromo-4-chlorothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-329)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-329_Int (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(4-chloro-5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-302, HBV-CSU-302-ISO-I & HBV-CSU-302-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-329 and corresponding bromo compound (see Table 2 for analytical data).

Scheme 45:

Synthesis of Cis-3-chloro-4-fluorophenyl)-2-methyl-5-(5-phenyl-1, 3, 4-thiadiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-304, HBV-CSU-304-ISO-I & HBV-CSU-304-ISO-II)

Synthesis of 1-(4-bromo-5-methylthiophen-2-yl) ethan-1-one (145)

To a stirred solution of compound 144 (5 g, 35.71 mmol) and NaOAc (3.22 g, 39.28 mmol) in water (300 mL), Br₂ (5.7 g, 35.71 mmol) was added drop wise at 0° C. The resulting reaction mixture was stirred at room temperature for 2 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was cooled to 0° C.; quenched by using aq. Sodium thiosulphate and extracted using ethyl acetate. The combined organic layers were collected, dried over anhydrous sodium sulphate, filtered and concentrated in vacuo to afford the title compound 145 (7.5 g, 96.77%) as a brown solid and used as such for the next step without further purification TLC: 40% EtOAc/hexane (R_f: 0.5); ¹H NMR (DMSO-d₆, 400 MHz): δ 7.88 (s, 1H), 2.46 (s, 3H), 2.38 (s, 3H); LCMS Calculated for C7H7BrOS: 217.94; Observed: 218.95 (M+1)⁺.

Synthesis of Methyl 4-(4-bromo-5-methylthiophen-2-yl)-2, 4-dioxobutanoate (146)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 6 g of compound 146 (57.30%, reaction scale is 7.5 g) as a brown solid. TLC: 40% EtOAc/hexane (R_f: 0.3). The crude material was used as such in the next reaction without further characterization.

Synthesis of Methyl 5-(4-bromo-5-methylthiophen-2-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (147)

Title compound was synthesized using general method B for the synthesis of cyclic sulfonamide described above to afford 8.9 g of compound 147 (crude, reaction scale is 6 g) as yellow solid. TLC: 40% EtOAc/hexane (R_f: 0.2); ¹H NMR (DMSO-d₆, 400 MHz): 8.01 (s, 1H), 6.92 (s, 1H), 3.84 (s, 3H), 2.42 (s, 3H); LCMS Calculated for C₁₀H₉BrN₂O₄S₂: 363.92; LCMS observed: 366.95 (M+2)⁺.

Synthesis of Methyl 5-(4-bromo-5-methylthiophen-2-yl)-2-methyl-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (148)

Title compound was synthesized using general method B for alkylation described above to afford 7 g of compound 148 (79.54%, reaction scale is 8.5 g) as a yellow solid. TLC: 40% EtOAc/hexanes (R_f: 0.3); ¹H NMR (DMSO-d₆, 400 MHz): δ 8.30 (s, 1H), 7.34 (s, 1H), 3.93 (s, 3H), 3.51 (s, 3H), 2.47 (s, 3H); LCMS Calculated for C₁₁H_nBrN₂O₄S₂: 377.93; LCMS observed: 380.95 (M+2)⁺.

Synthesis of 5-(4-bromo-5-methylthiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-304_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 148 and corresponding amine (see Table 1 for analytical data).

Synthesis of 5-(4-bromo-5-methylthiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-304_Int-I)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-304_Int-I (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-methyl-4-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-304, HBV-CSU-304-ISO-I & HBV-CSU-304-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-304_Int-I and corresponding bromo compound (see Table 2 for analytical data).

Scheme 46:

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-5-(5-ethyl-4-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-305, HBV-CSU-305-ISO-I & HBV-CSU-305-ISO-II) and Cis-5-(4-bromo-5-ethylthiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-334)

Synthesis of 1-(5-ethylthiophen-2-yl)ethan-1-one (150)

To a stirred solution of compound 149 (10 g, 89.13 mmol) in acetic anhydride (9.27 mL, 98.04 mmol) under inert atmosphere was added H₃PO₄ (0.464 mL, 8.913 mmol) portion wise at room temperature. The reaction was stirred at 100° C. for 1 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was poured on ice-cold slowly and extracted with ethyl acetate. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford crude compound 150 (12 g, crude) as brown liquid. TLC: 40% EtOAc/hexanes (R_f: 0.5). ¹H-NMR (DMSO-d₆, 400 MHz): δ 7.77 (d, J=4.6 Hz, 1H), 6.98 (d, J=3.6 Hz, 1H), 2.88-2.82 (m, 2H), 2.47 (s, 3H), 1.25 (t, J=7.2 Hz, 3H); LCMS Calculated for C₈H₁₀OS: 154.05; Observed: 155 (M+1)⁺.

Synthesis of 1-(4-bromo-5-methylthiophen-2-yl) ethan-1-one (151)

To a stirred solution of compound 150 (14 g, 90.90 mmol) and NaOAc (8.20 g, 99.99 mmol) in water (100 mL), Br₂ (4.69 mL, 90.90 mmol) was added drop wise at 0° C. The resulting reaction mixture was stirred at room temperature for 2 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was cooled to 0° C.; quenched by using aq. Sodium thiosulphate and extracted using ethyl acetate. The combined organic layers were collected, dried over anhydrous sodium sulphate, filtered and concentrated in vacuo to afford the title compound 151 (24 g, crude) as a brown sticky solid and used as such for the next step without further purification TLC: 40% EtOAc/hexane (R_f: 0.6); ¹H-NMR (DMSO-d₆, 400 MHz): δ 7.90 (s, 1H), 2.81-2.73 (m, 5H), 1.21-1.15 (m, 3H); LCMS Calculated for C₈H₉BrOS: 231.96; Observed: 232.90 (M+1)⁺.

Synthesis of Methyl 4-(4-bromo-5-ethylthiophen-2-yl)-2, 4-dioxobutanoate (152)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 12 g of compound 152 (crude, reaction scale is 24 g) as a light yellow solid. TLC: 40% EtOAc/hexane (R_f: 0.2). The crude material was used as such in the next reaction without further characterization.

Synthesis of Methyl 5-(4-bromo-5-ethylthiophen-2-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (153)

Title compound was synthesized using general method B for the synthesis of cyclic sulfonamide described above to afford 12 g of compound 153 (crude, reaction scale is 12 g) as a brown sticky solid. TLC: 40% EtOAc/hexane (R_f: 0.2); ¹H NMR (DMSO-d₆, 400 MHz): 8.03 (s, 1H), 6.94 (s, 1H), 6.32 (br.s, 1H), 3.85 (s, 3H), 2.83-2.81 (m, 2H), 1.24 (t, 7.2 Hz, 3H); LCMS Calculated for C₁₁H_nBrN₂O₄S₂: 377.93; LCMS observed: 380.90 (M+2)⁺.

Synthesis of Methyl 5-(4-bromo-5-ethylthiophen-2-yl)-2-methyl-2H-1, 2, 6-thiadiazine-3-carboxylate 1, 1-dioxide (154)

Title compound was synthesized using general method B for alkylation described above to afford 7.6 g of compound 154 (61.09%, reaction scale is 12 g) as a yellow solid. TLC: 40% EtOAc/hexanes (R_f: 0.4); ¹H NMR (DMSO-d₆, 400 MHz): 8.31 (s, 1H), 7.35 (s, 1H), 3.94 (s, 3H), 3.51 (s, 3H), 2.87-2.81 (m, 2H), 1.24 (t, J=7.2 Hz, 3H); LCMS Calculated for C₁₂H₁₃BrN₂O₄S₂: 391.95; LCMS observed: 395 (M+2)⁺.

Synthesis of 5-(4-bromo-5-ethylthiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-334_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using corresponding 154 and corresponding amine (see Table 1 for analytical data).

Synthesis of 5-(4-bromo-5-ethylthiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-334)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-334_Int-I (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-5-(5-ethyl-4-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-305, HBV-CSU-305-ISO-I & HBV-CSU-305-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-334 and corresponding bromo compound (see Table 2 for analytical data).

Scheme 47:

Synthesis of 5-(5-chloro-4-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-306, HBV-CSU-306-ISO-I & HBV-CSU-306-ISO-II) and 5-(4-bromo-5-chlorothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-330)

Synthesis of 1-(4-bromo-5-chlorothiophen-2-yl)ethan-1-one (156)

To a stirred solution of compound 155 (20 g, 124.51 mmol) in CHCl₃ (300 mL) at 0° C., AlCl₃ (48.14 g, 361.07 mmol) was added and stirred at same temperature for 10 min. To this solution, Br₂ (7.06 mL, 136.96 mmol) was added drop wise at 0° C. The resulting reaction mixture was stirred room temperature for 16 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was cooled to 0° C.; quenched by using aq. Sodium thiosulphate and extracted with ethyl acetate. The combined organic layers were collected, dried over anhydrous sodium sulphate and concentrated in vacuo to afford the title compound 156 (25 g, crude) as a yellow colored liquid and used as such for the next step without further purification. TLC: 40% EtOAc/hexane (R_f: 0.6); ¹H NMR (DMSO-d₆, 400 MHz): δ 7.50 (s, 1H), 2.51 (s, 3H).

Synthesis of Methyl 4-(4-bromo-5-chlorothiophen-2-yl)-2, 4-dioxobutanoate (157)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 22 g of compound 157 (crude, reaction scale is 32 g) as a brown colored liquid. TLC: 40% EtOAc/hexane (R_f: 0.3). The crude material was used as such in the next reaction without further characterization.

Synthesis of Methyl 5-(4-bromo-5-chlorothiophen-2-yl)-2H-1, 2, 6-thiadiazine-3-carboxylate 1,1-dioxide (158)

Title compound was synthesized using general method B for the synthesis of cyclic sulfonamide described above to afford 20 g of compound 158 (crude, reaction scale is 22 g) as light black solid. TLC: 40% EtOAc/hexane (R_f: 0.2); ¹H NMR (DMSO-d₆, 400 MHz): δ 8.00 (s, 1H), 6.75 (s, 1H), 3.81 (s, 3H).

Synthesis of Methyl 5-(4-bromo-5-chlorothiophen-2-yl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (159)

Title compound was synthesized using general method B for alkylation described above to afford 10 g of compound 159 (96%, reaction scale is 10 g) as a yellow solid. TLC: 40% EtOAc/hexanes (R_f: 0.4); ¹H NMR (DMSO-d₆, 400 MHz): δ 8.46 (s 1H), 7.39 (s, 1H), 3.94 (s, 3H), 3.53 (s, 3H); LCMS Calculated for C₁₀H₈BrClN₂O₄S₂: 397.88; LCMS observed: 400.90 (M+2)⁺.

Synthesis of 5-(4-bromo-5-chlorothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-2H-1, 2, 6-thiadiazine-3-carboxamide 1, 1-dioxide (HBV-CSU-330_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using corresponding 159 and corresponding amine (see Table 1 for analytical data).

Cis-5-(4-bromo-5-chlorothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-330)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-330_Int-I (see Table 2 for analytical data).

Cis-5-(5-chloro-4-(1-methyl-1I-pyrazol-4-yl)thiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-306, HBV-CSU-306-ISO-I & HBV-CSU-306-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-330 and corresponding bromo compound (see Table 2 for analytical data).

Scheme 48:

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(4-methyl-4H-1, 2, 4-triazol-3-yl)thiophen-2-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-324, HBV-CSU-324-ISO-I & HBV-CSU-324-ISO-II)

Synthesis of Methyl 5-(5-((3-chloro-4-fluorophenyl)carbamoyl)-6-methyl-1, 1-dioxido-1, 2, 6-thiadiazinan-3-yl)thiophene-2-carboxylate (160)

To a stirred solution of compound HBV-CSU-114 (5 g, 10.33 mmol) in MeOH:ACN (50 mL:12.5 mL) mixture under Ar atmosphere in an autoclave, TEA (3.13 g, 30.99 mmol) and dppf (0.57 g, 1.03 mmol) were added and purged with Ar for 15 min. To this, Pd(OAc)₂ (0.231 g, 1.03 mmol) was added and again purged with carbon monoxide and the resulting reaction mixture was heated in autoclave at 100° C. for 150 psi pressure for 6 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was filtered through a pad of Celite and filtrate was concentrated in vacuo. The residue obtained was diluted with water and extracted using ethyl acetate. The combined organic layers were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 30% EtOAc/hexane to afford the title compound 160 (2.5 g, 51.02%) as a brown solid. TLC: 40% EtOAc/hexane (R_f: 0.3); ¹H-NMR (DMSO-d₆, 400 MHz): δ 10.60 (s, 1H), 7.98-7.96 (m, 1H), 7.84-7.81 (m, 1H), 7.71 (d, J=4 Hz, 1H), 7.57-7.53 (m, 1H), 7.41 (t, J=9.2 Hz, 1H), 7.25 (d, J=4 Hz, 1H), 4.88-4.83 (m, 1H), 4.33-4.30 (m, 1H), 3.82 (s, 3H), 2.62 (s, 3H), 2.30-1.98 (m, 2H). LCMS Calculated for C₁₇H₁₇ClFN₃O₅S₂: 461.03; LCMS observed: 462.15 (M+1)⁺.

Synthesis of 5-(5-((3-chloro-4-fluorophenyl)carbamoyl)-6-methyl-1, 1-dioxido-1, 2, 6-thiadiazinan-3-yl)thiophene-2-carboxylic Acid (161)

To a stirred solution of compound 160 (1 g, 2.10 mmol) in THF (15 mL), aq. LiOH (0.22 g, 5.26 mmol, dissolved in 15 mL water) was added. The resulting reaction mixture was stirred at room temperature for 2 h. The reaction was monitored by TLC. After completion of the reaction, the volatiles were removed in vacuo. The residue was diluted with water and acidified with 2 N HCl to pH-2 and extracted with ethyl acetate. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford compound 161 (0.6 g, 61.8%) as a white solid. TLC: 50% EtOAc/hexanes (R_f: 0.1); LCMS Calculated for C₁₆H₁₅ClFN₃O₅S₂: 447.01; LCMS observed: 448.05 (M+1)⁺.

Synthesis of N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(4-methyl-5-thioxo-4, 5-dihydro-1H-1, 2, 4-triazol-3-yl)thiophen-2-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (162)

To a stirred solution compound 161 (0.6 g, 1.34 mmol) and N-methylhydrazinecarbothioamide (0.155 g, 1.47 mmol) in DMF (15 mL) under inert atmosphere, EDCI.HCl (38.06 g, 199.26 mmol) and HOBt (26.9 g, 199.25 mmol) were added. The reaction mixture was stirred at room temperature for 18 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was diluted with water and extracted with ethyl acetate. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain 0.71 g of crude compound which was used in the next step. The crude compound was dissolved in 5% NaOH solution and heated at 60° C. for 16 h. After completion, the reaction mixture was cooled to at 0° C.; acidified with 1 N HCl to pH-6 and extracted with ethyl acetate. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford the crude. The crude compound was purified by silica gel column chromatography using 50% EtOAc/hexanes to afford compound 162 (0.21 g, 27%) as an off white solid. TLC: 80% EtOAc/hexanes (R_f: 0.7);

¹H-NMR (DMSO-d₆, 400 MHz): δ 13.98 (s, 1H), 10.62 (s, 1H), 7.99-7.97 (m, 1H), 7.85-7.83 (m, 1H), 7.64-7.54 (m, 2H), 7.41 (t, J=8.8 Hz, 1H), 7.30-7.29 (m, 1H), 4.90-4.85 (m, 1H), 4.35-4.32 (m, 1H), 3.67 (s, 3H), 2.63 (s, 3H), 2.33-1.99 (m, 2H). LCMS Calculated for C₁₈H₁₈ClFN₆O₃S₃: 516.03; LCMS observed: 517.05 (M+1)⁺.

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(4-methyl-4H-1, 2, 4-triazol-3-yl)thiophen-2-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1, 1-dioxide (HBV-CSU-324, HBV-CSU-324-ISO-I & HBV-CSU-324-ISO-II)

To a stirred solution compound 162 (0.2 g, 0.387 mmol) in DCM (2 mL) at 0° C., H₂O₂ (0.028 g, 0.85 mmol) and acetic acid (0.5 mL) were added. The reaction mixture was stirred at room temperature for 3 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was basified with 2N NaOH to pH-10 and extracted with DCM. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford the crude. The crude compound was purified by silica gel column chromatography using 50% EtOAc/hexanes to afford compound HBV-CSU-324 (0.11 g, 59%) as a white solid. TLC: 80% EtOAc/hexanes (R_f: 0.2); (see Table 2 for analytical data).

Scheme 49:

Synthesis of N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(4-(4-methyl-4H-1,2,4-triazol-3-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-328, HBV-CSU-328-ISO-I & HBV-CSU-328-ISO-II)

Synthesis of methyl 5-(5-((3-chloro-4-fluorophenyl)carbamoyl)-6-methyl-1,1-dioxido-1,2,6-thiadiazinan-3-yl)thiophene-3-carboxylate (163)

To a stirred solution of compound HBV-CSU-146 (5 g, 10.33 mmol) in MeOH:ACN (50 mL:12.5 mL) mixture under Ar atmosphere in an autoclave, TEA (3.13 g, 30.99 mmol) and dppf (0.57 g, 1.03 mmol) were added and purged with Ar for 15 min. To this, Pd(OAc)₂ (0.231 g, 1.03 mmol) was added and again purged with carbon monoxide and the resulting reaction mixture was heated in autoclave at 100° C. for 150 psi pressure for 6 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was filtered through a pad of Celite and filtrate was concentrated in vacuo. The residue obtained was diluted with water and extracted using ethyl acetate. The combined organic layers were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 30% EtOAc/hexane to afford the title compound 163 (3 g, 63.8%) as a brown solid. TLC: 40% EtOAc/hexane (R_f: 0.2); ¹H-NMR (DMSO-d₆, 400 MHz): δ 10.57 (s, 1H), 8.37 (s, 1H), 7.97-7.95 (m, 1H), 7.75-7.72 (m, 1H), 7.57-7.53 (m, 1H), 7.46 (s, 1H), 7.40 (t, J=8.8 Hz, 1H), 4.83-4.77 (m, 1H), 4.32-4.28 (m, 1H), 3.78 (s, 3H), 2.63 (s, 3H), 2.30-2.27 (m, 1H), 2.16-1.97 (m, 1H); LCMS Calculated for C₁₇H₁₇ClFN₃O₅S₂: 461.03; LCMS observed: 462 (M+1)⁺.

Synthesis of 5-(5-((3-chloro-4-fluorophenyl)carbamoyl)-6-methyl-1,1-dioxido-1,2,6-thiadiazinan-3-yl)thiophene-3-carboxylic acid (164)

To a stirred solution of compound 163 (1 g, 2.16 mmol) in THF (10 mL), aq. LiOH (0.18 g, 5.4 mmol, dissolved in 10 mL water) was added. The resulting reaction mixture was stirred at room temperature for 2 h. The reaction was monitored by TLC. After completion of the reaction, the volatiles were removed in vacuo. The residue was diluted with water and acidified with 2 N HCl to pH-2 and extracted with ethyl acetate. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford compound 164 (0.9 g, 93.7%) as a white solid. TLC: 40% EtOAc/hexanes (R_f: 0.1); LCMS Calculated for C₁₆H₁₅ClFN₃O₅S₂: 447.01; LCMS observed: 448 (M+1)⁺.

Synthesis of N-(3-chloro-4-fluorophenyl)-2-methyl-5-(4-(4-methyl-5-thioxo-4,5-dihydro-1H-1,2,4-triazol-3-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (165)

To a stirred solution compound 164 (0.9 g, 2.01 mmol) and N-methylhydrazinecarbothioamide (0.22 g, 2.21 mmol) in DMF (10 mL) under inert atmosphere, EDCI.HCl (0.41 g, 2.21 mmol) and HOBt (0.28 g, 2.21 mmol) were added. The reaction mixture was stirred at room temperature for 18 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was diluted with water and extracted with ethyl acetate. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain crude compound which was used in the next step. The crude compound was dissolved in 5% NaOH solution and heated at 60° C. for 16 h. After completion, the reaction mixture was cooled to at 0° C.; acidified with 1 N HCl to pH-6 and extracted with ethyl acetate. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford the crude. The crude compound was purified by silica gel column chromatography using 20% EtOAc/hexanes to afford compound 165 (0.2 g, 18.18%) as an off white solid. TLC: 70% EtOAc/hexanes (R_f: 0.7); LCMS Calculated for C₁₈H₁₈ClFN₆O₃S₃: 516.03; LCMS observed: 517 (M+1)⁺.

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(4-(4-methyl-4H-1,2,4-triazol-3-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-328, HBV-CSU-328-ISO-I & HBV-CSU-328-ISO-II)

To a stirred solution compound 165 (0.2 g, 0.387 mmol) in DCM (10 mL) at 0° C., H₂O₂ (0.029 g, 0.85 mmol) and acetic acid (0.5 mL) were added. The reaction mixture was stirred at room temperature for 3 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was basified with 2N NaOH to pH-10 and extracted with DCM. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford the crude. The crude compound was purified by silica gel column chromatography using 50% EtOAc/hexanes to afford compound HBV-CSU-328 (0.1 g, 53.9%) as an off white solid. TLC: 5% MeOH/DCM (R_f: 0.1); (see Table 2 for analytical data).

Scheme 50:

Synthesis of 5-(5-(1H-imidazol-4-yl)thiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-1,1-dioxide (HBV-CSU-331-ISO-I & HBV-CSU-331-ISO-II)

Synthesis of N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-trityl-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (166)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-114 and (1-trityl-1H-imidazol-4-yl)boronic acid to afford compound 166 (0.75 g, 34.69%). TLC: 50% EtOAc/Hexane (R_f: 0.3); New spot isolated after column purification and used as such in the next reaction without chracterisation.

Synthesis of Cis-5-(5-(1H-imidazol-4-yl)thiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-331-ISO-I & HBV-CSU-331-ISO-II)

To a stirred solution of compound 166 (0.6 g, 0.842 mmol) in MeOH (10 mL), 1N HCl (10 mL) was added and refluxed for 1 h. The reaction was monitored by TLC. After completion, the reaction mixture was poured into ice cold water; basified with 10% NaHCO₃ solution and extracted with ethyl acetate. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford the crude. The crude compound was purified by silica gel column chromatography to afford compound HBV-CSU-331 (0.1 g, 25.64%)

(See Table 2 for analytical data).

Scheme 51:

Synthesis of Cis-5-(5-(1H-imidazol-4-yl)thiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-333-ISO-I & HBV-CSU-333-ISO-II)

Synthesis of N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-trityl-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (167)

To a mixture of compound HBV-CSU-122 (1 g, 2.06 mmol) and (1-trityl-1H-imidazol-4-yl)boronic acid (1.4 g, 4.12 mmol) in THF: H₂O (10 mL:2 mL) mixture, NaHCO₃ (0.51 g, 6.18 mmol) was added, purged with Ar for 15 min, followed by the addition of Pd (dppf)Cl₂ (0.15 g, 0.206 mmol) and stirred at 100° C. for 16 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was diluted with water and extracted with ethyl acetate. The combined organic layers were washed with 1N HCl, brine, dried over anhydrous sodium sulfate and evaporated under reduced pressure to afford the title compound 167 (0.75 g, 54%) as an off white solid. TLC: 30% EtOAc/hexanes (R_f: 0.2); New spot isolated after column purification and used as such in the next reaction without chracterisation.

Synthesis of 5-(5-(1H-imidazol-4-yl)thiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-333-ISO-I & HBV-CSU-333-ISO-II)

To a stirred solution of compound 167 (0.75 g, 1.05 mmol) in MeOH (5 mL) at 0° C., 1N HCl (5 mL) was added. The reaction mixture was stirred at 70° C. for 1 h. The reaction was monitored by TLC. After completion, the reaction mixture was diluted with water; basified with sat. NaHCO₃ solution and extracted with ethyl acetate. The combined organic layers were washed with brine, dried over anhydrous sodium sulfate and evaporated under reduced pressure. The crude compound was purified by prep. HPLC to afford the desired compound. (see Table 2 for analytical data).

Scheme 52:

Synthesis of Cis-5-(5-Bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-(methyl-d₃)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-336, HBV-CSU-336-ISO-I & HBV-CSU-336-ISO-II)

Synthesis of Ethyl 5-(5-Bromothiazol-2-yl)-2-(methyl-d₃)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (169)

Title compound was synthesized using general method B for alkylation described above to afford 4.82 g of Compound 169 (71%, reaction scale is 6.45 g) as a brown solid. TLC: 50% EtOAc/hexanes (R_f: 0.6); LCMS Calculated for C₁₀H₇D₃BrN₃O₄S₂: 381.95; LCMS observed: 385 (M+2)⁺.

Synthesis of 5-(5-Bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-(methyl-d₃)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-336_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using Compound 169 and corresponding amine (see Table 1 for analytical data).

Synthesis of 5-(5-Bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-(methyl-d₃)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-336, HBV-CSU-336-ISO-I & HBV-CSU-336-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-336_Int (see Table 2 for analytical data).

Scheme 53:

Synthesis of N-(3-chloro-4-fluorophenyl)-2-(methyl-d₃)-5-(5-(1-(methyl-d₃)-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-337-ISO-I & HBV-CSU-337-ISO-II) and N-(3-chloro-4-fluorophenyl)-2-(methyl-d₃)-5-(5-(1-methyl-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-338-ISO-I & HBV-CSU-338-ISO-II)

Cis-N-(3-Chloro-4-fluorophenyl)-2-(methyl-d₃)-5-(5-(1-(methyl-d₃)-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-337-ISO-I & HBV-CSU-337-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-336 and corresponding stannane (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-(methyl-d₃)-5-(5-(1-methyl-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-338-ISO-I & HBV-CSU-338-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-336 and corresponding stannane (see Table 2 for analytical data).

Scheme 54:

Synthesis of Cis-N-(3-Chloro-4-fluorophenyl)-2-(methyl-d₃)-5-(5-(1-(methyl-d₃)-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3,4,5-d₃-3-carboxamide 1,1-dioxide and Cis-N-(3-Chloro-4-fluorophenyl)-2-(methyl-d₃)-5-(5-(1-methyl-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3,4,5-d₃-3-carboxamide 1,1-dioxide (HBV-CSU-340-ISO-I & HBV-CSU-340-ISO-II)

Synthesis of 5-(5-Bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-(methyl-d₃)-1,2,6-thiadiazinane-3,4,5-d₃-3-carboxamide 1,1-dioxide (170)

To a stirred solution of compound HBV-CSU-336_Int (1 g, 2.07 mmol) in THF:D₂O (1:1, 10 mL) mixture at 0° C. under Ar atmosphere, NaBD₄ (0.173 g, 4.14 mmol) was added and stirred at room temperature for 2 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was concentrated in vacuo. The crude compound was purified by silica gel column chromatography using 5% MeOH/DCM to afford compound 170 (0.9 g, 88.75%) as a yellow solid. TLC: 30% EtOAc/hexanes (R_f. 0.2); ¹H-NMR (DMSO-d₆, 400 MHz): δ 10.59 (s, 1H), 7.98-7.93 (m, 2H), 7.90 (s, 1H), 7.58-7.54 (m, 1H), 7.40 (t, J=8.8 Hz, 1H), 2.12 (s, 1H). LCMS Calculated for C₁₄H₇D₆BrClFN₄O₃S₂: 487.97; LCMS observed: 491.1 (M+1)⁺.

Cis-N-(3-Chloro-4-fluorophenyl)-2-(methyl-d₃)-5-(5-(1-(methyl-d₃)-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3,4,5-d₃-3-carboxamide 1,1-dioxide (HBV-CSU-339-ISO-I & HBV-CSU-339-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using Compound 170 and corresponding stannane (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-(methyl-d₃)-5-(5-(1-methyl-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3,4,5-d₃-3-carboxamide 1,1-dioxide (HBV-CSU-340-ISO-I & HBV-CSU-340-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using Compound 170 and corresponding stannane (see Table 2 for analytical data).

Scheme 55:

Synthesis of Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(1-(methyl-d₃)-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3,4,5-d₃-3-carboxamide 1,1-dioxide (HBV-CSU-341-ISO-I & HBV-CSU-341-ISO-II)

Cis-5-(5-Bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3,4,5-d₃-3-carboxamide 1,1-dioxide (171)

To a stirred solution of compound HBV-CSU-122-amide (1.2 g, 2.5 mmol) in THF:D₂O (1:1, 10 mL) mixture at 0° C. under Ar atmosphere, NaBD₄ (0.209 g, 5 mmol) was added and stirred at room temperature for 45 min. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was concentrated in vacuo. The crude compound was purified by silica gel column chromatography using 100% EtOAc/hexanes to afford compound 171 (1.1 g, 90.9%) as a light yellow solid. TLC: 40% EtOAc/hexanes (R_f: 0.5); ¹H-NMR (DMSO-d₆, 400 MHz): δ 10.58 (s, 1H), 7.97-7.94 (m, 2H), 7.89 (s, 1H), 7.57-7.54 (m, 1H), 7.40 (t, J=8.8 Hz, 1H), 2.63 (s, 3H), 2.12 (s, 1H); LCMS Calculated for C₁₄H₁₀D₃BrClFN₄O₃S₂: 484.95; LCMS observed: 488 (M+2)⁺.

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(1-(methyl-d₃)-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3,4,5-d₃-3-carboxamide 1,1-dioxide (HBV-CSU-341-ISO-I & HBV-CSU-341-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using Compound 171 and corresponding stannane (see Table 2 for analytical data).

Scheme 56:

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(1-methyl-111-benzo[d]imidazol-5-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-360, HBV-CSU-360-ISO-I & HBV-CSU-360-ISO-II)

Synthesis of N-methoxy-N, 1-dimethyl-1H-benzo[d]imidazole-5-carboxamide (173)

To a stirred solution acid compound 172 (6.7 g, 38.06 mmol) and N,O-dimethylhydroxylamine (5.57 g, 57.09 mmol) in DCM (70 mL) at 0° C. was added DIPEA (13.53 mL, 76.13 mmol), stirred for 15 min, followed by addition of HATU (21.69 g, 57.09 mmol), again stirred for 15 min. The reaction mixture was then stirred at room temperature for overnight. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was diluted with ice cold water and extracted with DCM. The combined organic layers were dried over anhydrous sodium sulphate and concentrated under reduced pressure to afford a crude compound. The crude compound was purified by silica gel column chromatography using 2% MeOH/DCM to afford the title compound 173 (8.1 g, 98.78%) as a brown liquid. TLC: 5% MeOH/DCM (R_f: 0.3). ¹H LCMS Calculated for C_HH₁₃N₃O₂: 219.10; LCMS observed: 219.95 (M+1)⁺.

Synthesis of 1-(1-methyl-1H-benzo[d]imidazol-5-yl)ethan-1-one (174)

To a stirred solution of compound 173 (8.1 g, 36.95 mmol) in anhydrous THF (80 mL) under inert atmosphere was added methyl magnesium bromide (24.77 mL, 73.97 mmol, 3 M sol. in diethyl ether) dropwise for 15 min at 0° C., followed by warming to room temperature and stirring for 3 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with saturated ammonium chloride solution (50 mL) and extracted with ethyl acetate. The combined organic layers were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. The crude compound was purified by silica gel column chromatography using 2% MeOH/DCM to afford the title compound 174 (5.65 g, 87.59%) as an off white solid. TLC: 5% MeOH/DCM (R_f: 0.4); ¹H NMR (400 MHz, DMSO-d₆): δ 8.34-8.32 (m, 2H), 7.90 (d, J=8.4 Hz, 1H), 7.66 (d, J=8.8 Hz, 1H), 3.87 (s, 3H), 2.64 (s, 3H); LCMS Calculated for C₁₀H₁₀N₂O: 174.08; Observed: 175.10 (M+1)⁺.

Synthesis of Methyl 4-(1-methyl-1H-benzo[d]imidazol-5-yl)-2,4-dioxobutanoate (175)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 3.8 g of Compound 175 (crude, reaction scale is 5 g) as a brown solid. TLC: 80% EtOAc/hexane (R_f: 0.1); LCMS Calculated for C₁₃H₁₂N₂O₄: 260.08; Observed: 261 (M+1)⁺.

Synthesis of Methyl 5-(1-methyl-1H-benzo[d]imidazol-5-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (176)

Title compound was synthesized using general method B for the synthesis of cyclic sulfonamide described above to afford 2 g of Compound 176 (42.82%, reaction scale is 3.8 g) as a yellow solid. TLC: 5% MeOH/DCM (R_f: 0.1; LCMS observed for C₁₃H₁₂N₄O₄S: 320.06 (M+1)⁺. Observed: 320.95 (M+1)⁺.

Synthesis of Methyl 2-methyl-5-(1-methyl-1H-benzo[d]imidazol-5-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (177)

Title compound was synthesized using general method B for alkylation described above to afford 1.3 g of Compound 177 (crude, reaction scale is 1.8 g); TLC: 5% MeOH/DCM (R_f: 0.2); LCMS Calculated for C₁₄H₁₄N₄O₄S: 334.07; LCMS observed: 335 (M+1)⁺.

Synthesis of N-(3-chloro-4-fluorophenyl)-2-methyl-5-(1-methyl-1H-benzo[d]imidazol-5-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-360_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using Compound 177 and corresponding amine (see Table 1 for analytical data).

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(1-methyl-1H-benzo[d]imidazol-5-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-360, HBV-CSU-360-ISO-I & HBV-CSU-360-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-360_Int (see Table 2 for analytical data).

Scheme 57:

Synthesis of Cis-5-(benzo[d]thiazol-5-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-361)

Synthesis of N-methoxy-N-methylbenzo[d]thiazole-5-carboxamide (179)

To a stirred solution of compound 178 (4 g, 22.32 mmol) in DCM (50 mL) at 0° C., DIPEA (7.77 mL, 44.64 mmol) and HATU (12.72 g, 33.48 mmol) were added and stirred for 15 min.

To this solution, N,O-dimethylhydroxylamine hydrochloride (3.26 g, 33.48 mmol) was added. The reaction mixture was stirred at room temperature for 16 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was diluted with ice cold water and extracted with DCM. The combined organic layers were dried over anhydrous sodium sulphate and concentrated under reduced pressure to afford a crude compound. The crude compound was purified by silica gel column chromatography using 50% EtOAc/hexane to afford the title compound 179 (3.7 g, 60.48%) as a white solid. TLC: 60% EtOAc/hexane (R_f: 0.3). LCMS Calculated for C₁₀H₁₀N₂O₂S: 222.05; LCMS observed: 222.95 (M+1)⁺.

Synthesis of 1-(benzo[d]thiazol-5-yl)ethan-1-one (180)

To a stirred solution of compound 179 (3.7 g, 16.6 mmol) in anhydrous THF (40 mL) under inert atmosphere was added methyl magnesium bromide (11.09 mL, 33.3 mmol, 3 M sol. in diethyl ether) dropwise for 15 min at 0° C., followed by warming to room temperature and stirring for 2 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with saturated ammonium chloride solution and extracted with ethyl acetate. The combined organic layers were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford the title compound 180 (2.4 g, 81.35%) as yellow solid. TLC: 30% EtOAc/hexane (R_f: 0.4). LCMS Calculated for C₉H₇NOS:177.02; Observed: 177.90 (M+1)⁺.

Synthesis of Methyl 4-(benzo[d]thiazol-5-yl)-2,4-dioxobutanoate (181)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 3 g of Compound 181 (crude, reaction scale is 2.3 g); TLC: 30% EtOAc/hexane (R_f: 0.1); LCMS Calculated for C₁₂H₉NO₄S: 263.03; Observed: 263.95 (M+1)⁺.

Synthesis of Methyl 5-(benzo[d]thiazol-5-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (182)

Title compound was synthesized using general method B for cyclisation described above to afford 0.5 g of Compound 182 (13.57%, reaction scale is 3 g) as a yellow solid. TLC: 10% MeOH/DCM (R_f: 0.2); ¹H NMR (DMSO-d₆, 400 MHz): δ 9.49 (s, 1H), 8.62 (s, 1H), 8.28 (d, J=8.4 Hz, 1H), 8.06 (d, J=8.4 Hz, 1H), 6.94 (s, 1H), 3.86 (s, 3H); LCMS Calculated for C₁₂H₉N₃O₄S₂: 323.00; LCMS observed: 323.9 (M+1)⁺.

Synthesis of Methyl 5-(benzo[d]thiazol-5-yl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (183)

Title compound was synthesized using general method B for alkylation described above to afford 0.3 g of Compound 183 (58%, reaction scale is 0.5 g) as a yellow solid. TLC: 30% EtOAc/hexane (R_f: 0.1); LCMS Calculated for C₁₃H₁₁N₃O₄S₂: 337.02; LCMS observed: 338 (M+1)⁺.

Synthesis of 5-(benzo[d]thiazol-5-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-361_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using Compound 183 and corresponding amine (see Table 1 for analytical data).

Synthesis of Cis-5-(benzo[d]thiazol-5-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-361)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-361_Int (see Table 2 for analytical data).

Scheme 58:

Synthesis of Cis-5-(benzo[d]thiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-364)

Synthesis of 1-(benzo[d]thiazol-2-yl)ethan-1-one (185)

To a stirred solution of compound 184 (10 g, 74.07 mmol) in anhydrous THF (100 mL) under inert atmosphere was added n-butyl lithium (32.5 mL, 81.48 mmol, 2.5 M in hexane) dropwise for 15 min at −78° C. and, followed by stirring for 1 h. To this was added N,N-dimethylacetamide (6.44 g, 74.07 mmol) at −78° C. and stirred for 1 h. Then Conc. HCl (15 mL) was added at to 0° C. and stirring for 2 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was poured on water and extracted with EtOAc (3×100 mL). The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 4% EtOAc/hexanes to afford compound 185 (3.1 g, 23.64%) as a off white solid. TLC: 10% EtOAc/hexanes (R_f: 0.3); ¹H NMR (DMSO-d₆, 400 MHz): δ 8.26-8.23 (m, 2H), 7.69-7.61 (m, 2H), 2.76 (s, 3H); LCMS Calculated for C₉H₇NOS: 177.02; Observed: 178 (M+1)⁺.

Synthesis of Methyl 4-(benzo[d]thiazol-2-yl)-2,4-dioxobutanoate (186)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 2.7 g of Compound 186 (crude, reaction scale is 3 g); LCMS Calculated for C₁₂H₉NO₄S: 263.03; Observed: 264.1 (M+1)⁺.

Synthesis of Methyl 5-(benzo[d]thiazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (187)

Title compound was synthesized using general method B for cyclisation described above to afford 0.53 g of Compound 187 (28.80%, reaction scale is 1.5 g) as an off white solid. 50% EtOAc/hexanes (R_f: 0.1); LCMS Calculated for C₁₂H₉N₃O₄S₂: 323.00; LCMS observed: 324 (M+1)⁺.

Synthesis of Methyl 5-(benzo[d]thiazol-2-yl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (188)

Title compound was synthesized using general method A for alkylation described above to afford 0.37 g of Compound 188 (59%, reaction scale is 0.6 g) as an off white solid. TLC: 20% EtOAc/hexanes (R_f: 0.5); LCMS Calculated for C₁₃H₁₁N₃O₄S₂: 337.02; LCMS observed: 338.05 (M+1)⁺.

Synthesis of 5-(benzo[d]thiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-364_Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using Compound 188 and corresponding amine (see Table 1 for analytical data).

Synthesis of Cis-5-(benzo[d]thiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-364)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-364_Int (see Table 2 for analytical data).

Scheme 59:

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(1-methyl-1H-benzo[d]imidazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-368)

Synthesis of N-methoxy-N-methyl-1H-benzo[d]imidazole-2-carboxamide (190)

To a stirred solution of compound 189 (24 g, 148 mmol) in DCM (250 mL) under inert atmosphere, DIPEA (51.58 mL, 296 mmol) and HATU (84.39 g, 222 mmol) were added. To this solution, N,O-dimethylhydroxylamine hydrochloride (21.66 g, 222 mmol) was added and stirred at room temperature for 16 h. The progress of the reaction was monitored by TLC. After completion of the reaction, the reaction mixture was poured into ice-cold water and extracted using DCM. The combined organic extracts were washed with brine, dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to obtain the crude. The crude was purified through silica gel column chromatography using 50% EtOAc/hexanes to afford compound 190 (15 g, 49.40%) as a white solid. TLC: 5% MeOH/DCM (R_f: 0.5); ¹H NMR (400 MHz, DMSO-d₆): δ 13.19 (s, 1H), 7.84 (d, J=8.4 Hz, 1H), 7.54 (d, J=7.6 Hz, 1H), 7.34-7.24 (m, 2H), 3.83 (s, 6H); LCMS Calculated for C₁₀H_nN₃O₂: 205.09; Observed: 206 (M+1)⁺.

Synthesis of 1-(1H-benzo[d]imidazol-2-yl)ethan-1-one (191)

To a stirred solution of compound 190 (15 g, 73.13 mmol) in anhydrous THF (200 mL) under inert atmosphere was added methyl magnesium bromide (48.75 mL, 146.3 mmol, 3 M sol. in diethyl ether) dropwise for 15 min at 0° C. The reaction mixture was stirred at 0° C. for 2 h. The progress of the reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with saturated ammonium chloride solution and extracted with ethyl acetate The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford compound 191 (7 g, 60%) as a yellow solid. TLC: 30% EtOAc/hexanes (R_f: 0.5); ¹H NMR (400 MHz, DMSO-d₆): δ δ 13.28 (s, 1H), 7.82-7.80 (m, 1H), 7.55-7.53 (m, 1H), 7.35-7.30 (m, 2H), 2.69 (s, 3H); LCMS Calculated for C₉H₈N₂O: 160.06; Observed: 160.95 (M+1)⁺.

Synthesis of 1-(1-methyl-1H-benzo[d]imidazol-2-yl)ethan-1-one (192)

To a stirred solution of compound 191 (5.5 g, 34.37 mmol) in 2N NaOH (165 mL) at 0° C., dimethyl sulfate (5.63 g, 44.68 mmol) was added and reaction was stirred the at room temperature for 1 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was acidifed with 1N HCl and extracted with ethyl acetate. The combined organic extracts were dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford compound 192 (4 g, 66.88%) as a off white solid. TLC: 20% EtOAc/hexanes (R_f: 0.7); ¹H NMR (400 MHz, DMSO-d₆): δ 7.82 (d, J=8.4 Hz, 1H), 7.21 (d, J=8.4 Hz, 1H), 7.45 (t, J=8.0 Hz, 1H), 7.35 (d, J=7.6 Hz, 1H), 4.07 (s, 3H), 2.73 (s, 3H); LCMS Calculated for C₁₀H₁₀N₂O: 174.08; Observed: 174.90 (M+1)⁺.

Synthesis of Methyl 4-(1-methyl-1H-benzo[d]imidazol-2-yl)-2,4-dioxobutanoate (193)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 3.3 g (51%, reaction scale is 4 g); TLC: 5% MeOH/DCM (R_f: 0.1); ¹LCMS Calculated for C₁₃H₁₂N₂O₄: 260.08; Observed: 260.8 (M+1)⁺.

Synthesis of Methyl 5-(1-methyl-1H-benzo[d]imidazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (194)

Title compound was synthesized using general method B for cyclisation described above to afford 2.1 g of Compound 194 (52%, reaction scale is 3.3 g) as an off white solid. TLC: 10% MeOH/DCM (R_f: 0.1); ¹H NMR (400 MHz, DMSO-d₆): δ 7.97 (d, J=7.6 Hz, 1H), 7.82-7.78 (m, 1H), 7.63-7.60 (m, 2H), 7.30-7.04 (m, 1H), 6.85 (s, 1H), 4.28 (s, 3H), 3.84 (s, 3H); LCMS Calculated for C₁₃H₁₂N₄O₄S: 320.06; LCMS observed: 320.95 (M+1)⁺.

Synthesis of Methyl 2-methyl-5-(1-methyl-1H-benzo[d]imidazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (195)

Title compound was synthesized using general method B for alkylation described above to afford 1.1 g of Compound 195 (51%, reaction scale is 2.1 g) as a yellow solid. TLC: 5% MeOH/DCM (R_f: 0.5); NMR (400 MHz, DMSO-d6): δ 7.85 (d, J=8.0 Hz, 1H), 7.76 (d, J=8.4 Hz, 1H), 7.73 (s, 1H), 7.49 (t, J=8.4 Hz, 1H), 7.38 (t, J=8.4 Hz, 1H), 4.21 (s, 3H), 3.97 (s, 3H), 3.60 (s, 3H); LCMS Calculated for C₁₄H₁₄N₄O₄S: 334.07; LCMS observed: 334.95 (M+1)⁺.

Synthesis of N-(3-chloro-4-fluorophenyl)-2-methyl-5-(1-methyl-1H-benzo[d]imidazol-2-yl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-368_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using Compound 195 and corresponding amine (see Table 1 for analytical data).

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(1-methyl-1H-benzo[d]imidazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-368)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-368_Int (see Table 2 for analytical data).

Scheme 60:

Synthesis of (3S,5R)—N-(3-bromo-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-369) and (3S, 5R)—N-(3-bromo-4-fluorophenyl)-5-(5-bromothiazol-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-383)

Synthesis of (3S, 5R)—N-(3-bromo-4-fluorophenyl)-5-(5-bromothiazol-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-383)

The above titled compound has been synthesized by following the general procedure (Method A, amide coupling) described above for amidation by using Compound 196 and corresponding amine (see Table 1 for analytical data).

Synthesis of (3S, 5R)—N-(3-bromo-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-369)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-383 and corresponding stannane (see Table 2 for analytical data).

Scheme 61:

Synthesis of Cis-5-(5-bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-(methyl-d₃)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-370, HBV-CSU-370-ISO-I & HBV-CSU-370-ISO-I)

Synthesis of Methyl 5-(5-bromothiophen-2-yl)-2-(methyl-d3)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (197)

Title compound was synthesized using general method B for alkylation described above to afford 15 g of Compound 197 (71.53%, reaction scale is 20 g) as a brown solid. TLC: 10% MeOH/DCM (R_f: 0.6); LCMS Calculated for C₁₀H₆D₃BrN₂O₄S₂: 366.94; LCMS observed: 373 (M+2)⁺.

Synthesis of 5-(5-bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-(methyl-d₃)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-370_Int)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using Compound 197 and corresponding amine (see Table 1 for analytical data).

Synthesis of Cis-5-(5-bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-(methyl-d₃)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-370, HBV-CSU-370-ISO-I & HBV-CSU-370-ISO-I)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-370_Int (see Table 2 for analytical data).

Scheme 62:

Synthesis of Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(1-(methyl-d₃)-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3,4,5-d₃-3-carboxamide 1,1-dioxide (HBV-CSU-371, HBV-CSU-371-ISO-I & HBV-CSU-371-ISO-I)

Cis-5-(5-Bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3,4,5-d₃-3-carboxamide 1,1-dioxide (HBV-CSU-371, HBV-CSU-371-ISO-I & HBV-CSU-371-ISO-I)

To a stirred solution of compound HBV-CSU-114-amide (3 g, 6.25 mmol) in THF:D₂O (1:1, 30 mL) mixture at 0° C. under Ar atmosphere, NaBD₄ (0.523 g, 12.5 mmol) was added and stirred at room temperature for 30 min. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was concentrated in vacuo. The crude compound was purified by silica gel column chromatography to afford compound HBV-CSU-371 (2 g, 66.6%) as a white solid. TLC: 50% EtOAc/hexanes (R_f: 0.3);

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3,4,5-d₃-3-carboxamide 1,1-dioxide (HBV-CSU-375, HBV-CSU-375-ISO-I & HBV-CSU-375-ISO-I)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-371 and corresponding stannane (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-methyl-5-(5-(1-(methyl-d₃)-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3,4,5-d₃-3-carboxamide 1,1-dioxide (HBV-CSU-376, HBV-CSU-376-ISO-I & HBV-CSU-376-ISO-I)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-371 and corresponding stannane (see Table 2 for analytical data).

Scheme 63:

Synthesis of Cis-5-(5-bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-(methyl-d₃)-1,2,6-thiadiazinane-3,4,5-d₃-3-carboxamide 1,1-dioxide (HBV-CSU-372, HBV-CSU-372-ISO-I & HBV-CSU-372-ISO-I), Cis-N-(3-chloro-4-fluorophenyl)-2-(methyl-d₃)-5-(5-(1-methyl-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3,4,5-d3-3-carboxamide HBV-CSU-377, HBV-CSU-377-ISO-I & HBV-CSU-377-ISO-I) and Cis-N-(3-chloro-4-fluorophenyl)-2-(methyl-d₃)-5-(5-(1-(methyl-d₃)-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3,4,5-d₃-3-carboxamide 1,1-dioxide (HBV-CSU-378, HBV-CSU-378-ISO-I & HBV-CSU-378-ISO-I)

Synthesis of Cis-5-(5-bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-(methyl-d₃)-1,2,6-thiadiazinane-3,4,5-d₃-3-carboxamide 1,1-dioxide (HBV-CSU-372, HBV-CSU-372-ISO-I & HBV-CSU-372-ISO-I, E17107-097)

To a stirred solution of compound HBV-CSU-370_Int (1.5 g, 3.11 mmol) in THF:D₂O (1:1, 20 mL) mixture at 0° C. under Ar atmosphere, NaBD₄ (0.261 g, 6.22 mmol) was added and stirred at room temperature for 2 h. The progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was concentrated in vacuo. The crude compound was purified by silica gel column chromatography using 2% MeOH/DCM to afford compound HBV-CSU-372 (1.2 g, 78.94%) as an off white solid. TLC: 30% EtOAc/hexanes (R_f: 0.5).

Cis-N-(3-Chloro-4-fluorophenyl)-2-(methyl-d₃)-5-(5-(1-methyl-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3,4,5-d3-3-carboxamide HBV-CSU-377, HBV-CSU-377-ISO-I & HBV-CSU-377-ISO-I)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-372 and corresponding stannane (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-(methyl-d₃)-5-(5-(1-(methyl-d₃)-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3,4,5-d₃-3-carboxamide 1,1-dioxide (HBV-CSU-378, HBV-CSU-378-ISO-I & HBV-CSU-378-ISO-I)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-372 and corresponding stannane (see Table 2 for analytical data).

Scheme 64:

Synthesis of Cis-N-(3-Chloro-4-fluorophenyl)-2-(methyl-d₃)-5-(5-(1-methyl-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-373-ISO-I & HBV-CSU-373-ISO-I) and Cis-N-(3-Chloro-4-fluorophenyl)-2-(methyl-d₃)-5-(5-(1-(methyl-d₃)-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-374-ISO-I & HBV-CSU-374-ISO-I)

Cis-N-(3-Chloro-4-fluorophenyl)-2-(methyl-d₃)-5-(5-(1-methyl-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-373-ISO-I & HBV-CSU-373-ISO-I)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-370 and corresponding stannane (see Table 2 for analytical data).

Cis-N-(3-Chloro-4-fluorophenyl)-2-(methyl-d₃)-5-(5-(1-(methyl-d₃)-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-374-ISO-I & HBV-CSU-374-ISO-I)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-370 and corresponding stannane (see Table 2 for analytical data).

Scheme 65:

Synthesis of Cis-5-(5-bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-(methyl-d₃)-1,2,6-thiadiazinane-3,4,5-d₃-3-carboxamide 1,1-dioxide (HBV-CSU-379, HBV-CSU-379-ISO-I & HBV-CSU-379-ISO-I)

Synthesis of methyl-d₃ 4-methylbenzenesulfonate (199)

Titled compound was prepared using the reported method in Journal of Organic Chemistry, 81(17), 7675-7684; 2016.

Synthesis of 4-Bromo-1-(methyl-d₃)-1H-pyrazole (200)

To a stirred solution of 4-bromo-1H-pyrazole (5 g, 34.01 mmol) in DMF (30 mL), CS₂CO₃ (33.24 g, 102.05 mmol) was added and stirred for 10 min. To this solution, compound 199 (8.36 g, 51.02 mmol) was added and the reaction mixture was stirred at room temperature for 16 h. The progress of the reaction was monitored by TLC. the After completion, the reaction mixture was diluted with water and extracted with ethyl acetate. The combined organic layers were washed with brine, dried over anhydrous sodium sulfate and evaporated under reduced pressure to afford the title compound 200 (4 g, 72.72%) as a white solid. TLC: 50% EtOAc/hexanes (R_f: 0.3); LCMS Calculated for C₄H₂D₃BrN₂: 162.98; LCMS observed: 165.95 (M+2)⁺.

Synthesis of 1-(methyl-d₃)-4-(tributylstannyl)-1H-pyrazole (201)

To a stirred solution of compound 200 (1 g, 6.09 mmol) in diethyl ether (10 mL) at −78° C. under Ar atmosphere, n-BuLi (2.5 M, 2.68 mL, 6.69 mmol) was added dropwise and stirred at same temperature for 30 min. To this solution, tributyl tin chloride (1.18 mL, 6.69 mmol) was added at −78° C. slowly, which was then warmed to −60° C. and stirred for 1 h. The resulting reaction mixture was stirred at room temperature for 1 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with saturated ammonium chloride and extracted with ethyl acetate. The combined organic extracts were washed with water, brine, then dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to obtain the crude stannane compound. The crude compound was purified by silica gel column chromatography to afford the title compound 201 (0.5 g, 21.92%) as a yellow oil. TLC: 20% EtOAc/hexanes (R_f: 0.5) LCMS Calculated for C₁₆H₂₉D₃N₂Sn: 375.18; LCMS observed: 376.1 (M+1)⁺.

Synthesis of Cis-N-(3-Chloro-4-fluorophenyl)-2-(methyl-d₃)-5-(5-(1-(methyl-d₃)-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3,4,5-d₃-3-carboxamide 1,1-dioxide (HBV-CSU-379, HBV-CSU-379-ISO-I & HBV-CSU-379-ISO-I)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-372 and compound 201 (see Table 2 for analytical data).

Scheme 66:

Synthesis of (3S, 5R)-5-(5-Bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-114-ISO-I; ATH Approach)

To a solution of HBV-CSU-114_Int (1 eq.) & Noyori catalyst 3a (0.1 eq.) in dichloromethane (0.2M) was added 5 eq. of formic acid {85% w/w in water} followed by 2 eq. of DIPEA. The reaction mixture was stirred at room temperature for 16 h. The progress of reaction was monitored by TLC and LCMS. After completion, the reaction mixture was diluted with water and extracted using ethyl acetate. The combined organic layer was dried over anhydrous sodium sulphate, filtered and concentrated to give crude material which was purified using combiflash chromatography to afford desired product. The enantioselectivity was confirmed using chiral HPLC.

General Protocol for the Synthesis of Noyori Catalyst:

A mixture of [RuCl₂(η6-p-cycmene)]₂ (1 eq.), (1S, 2S)-(+)-N-p-Tosyl-1,2-(2 eq.) and triethyl amine (4 eq.) in propanol (25V) was heated at 80° C. for 2 h. The solvents was evaporated and the solid material obtained after filtration was washed with water and dried under vacuo to afford {Noyori (S, 5) catalyst} i.e. RuCl [(1S, 2S)-p-TsNCH (C₆H₅) NH₂] (η6-p-cycmene) as orange colored solid. The catalyst was recrystallized using methanol. The desired catalyst formation was confirmed by ¹H NMR and LCMS (see Table 2 for analytical data).

Scheme 67:

Synthesis of (3S, 5R)—N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-266-ISO-I; Resolution of Acid by Cinchonine Approach)

Synthesis of 5-(5-bromothiophen-2-yl)-2-methyl-2H-1, 2, 6-thiadiazine-3-carboxylic Acid 1,1-dioxide (219)

To a solution of compound 58 (65 g, 178.08 mmol) in 700 mL (10.8V) of CH₃CN: H₂O (1:1) at 0° C. was added TEA (124 mL, 890.41 mmol) and the resulting reaction mixture was stirred at the same temperature till clear solution was observed (usually 4-6 h). The progress of reaction was monitored by TLC. After completion, the reaction mixture was concentrated under reduced pressure, and residue obtained was acidified with 6N HCl and extracted with ethyl acetate. The combined organic layer was dried over anhydrous sodium sulphate, filtered and concentrated under reduced pressure to afford Compound 219 (57 g, 91%) as a brown solid. TLC: 5% MeOH/DCM (R_f: 0.3); ¹H NMR (DMSO-d₆, 400 MHz): δ 11.0 (br.s, 1H), 8.10 (d, J=4.0 Hz, 1H), 7.45 (d, J=4.0 Hz, 1H), 7.19 (s, 1H), 3.51 (s, 3H); HPLC purity: 98.85%, LCMS purity: 97.50%; LCMS Calculated for C₉H₇BrN₂O₄S₂: 349.90; LCMS observed: 352.90 (M+2)⁺.

Synthesis of 5-(5-bromothiophen-2-yl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxylic Acid 1,1-dioxide (220)

To a stirred solution of Compound 219 (40 g, 114.3 mmol) in 500 mL of EtOH: THF (9:1) at 0° C. under Ar atmosphere, NaBH₄ (8.6 g, 228.6 mmol) was added and the reaction mixture was stirred at room temperature for 3 h. The progress of the reaction was monitored by TLC & LCMS. After completion, the reaction mixture was concentrated in vaccuo. The residue was diluted with water and extracted using diethyl ether. The combined organic layers were collected; dried over anhydrous sodium sulphate, filtered and concentrated in vaccuo to afford Compound 220 (Cis racemic) (32 g, 75%) as a light brown solid. TLC: 10% MeOH/DCM (Rf: 0.1); ¹H NMR (DMSO-d₆, 400 MHz): δ 11.39 (s, 1H), 7.60 (d, J=9.2 Hz, 1H), 7.11 (d, J=4.0 Hz, 1H), 6.97 (d, J=4.0 Hz, 1H), 4.76-4.70 (m, 1H), 4.20 (dd, J=12.0, 2.8 Hz, 1H), 2.60 (s, 3H), 2.21-2.15 (m, 1H), 1.98-1.89 (m, 1H); HPLC purity: 99.23%, LCMS purity: 99.87%; LCMS Calculated for C₉H₁₁BrN₂O₄S₂: 353.93; LCMS observed: 354.90 (M+1)⁺.

Synthesis of (3S, 5R)-5-(5-bromothiophen-2-yl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxylic Acid 1,1-dioxide (Compound 221) & (3R, 5S)-5-(5-bromothiophen-2-yl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxylic Acid 1,1-dioxide (Compound 222)

Racemic Compound 220 (40.0 g, 112.9 mmol) was dissolved in 1.2 L of IPA (˜30V) after which Cinchonine (33.3 g, 112.9 mmol) was added and the reaction mixture was heated at 90° C. for 2 h (Clear solution was observed). The solid was precipitated out at the same temperature after 10-20 min. The reaction mixture was then allowed to cool down to accelerate the crystallization and kept at room temperature for overnight. After crystallization both mother liquor and crystals were analyzed by HPLC on chiral amylose SA column (eluent; DCM:MeOH 50:50) after acidification followed by extraction to determine the relative amount of Compound 221-salt and Compound 222-salt. The analysis showed enantiomeric enrichment of both the crystals. Then both isomers were isolated (#211-salt, 38 g) and the mother liquor (#222-salt, 43 g).

A suspension of 38 g of Compound 221-salt in 150 mL of ethyl acetate was acidified to a pH of 1.0 with 4N aq. HCl at 0° C. The organic layer was separated and aqueous layer was further extracted with ethyl acetate (3×50 mL). The combined organic layers were concentrated, dried over anhydrous sodium sulphate, filtered and concentrated to give 16 g of Compound 221 (Chiral HPLC 95.5%).

Analytical Data for Compound 221:

¹H NMR (DMSO-d₆, 400 MHz): δ 13.41 (s, 1H), 7.59 (d, J=8.8 Hz, 1H), 7.10 (d, J=4.0 Hz, 1H), 6.97-6.96 (m, 1H), 4.76-4.70 (m, 1H), 4.22-4.19 (m, 1H), 2.59 (s, 3H), 2.19-2.15 (m, 1H), 1.98-1.88 (m, 1H); HPLC purity: 99.53%; HPLC chiral purity: 94.29%;

Analytical Data for Compound 222:

¹H NMR (DMSO-d₆, 400 MHz): δ 13.02 (s, 1H), 7.60 (d, J=8.8 Hz, 1H), 7.11 (d, J=4.0 Hz, 1H), 6.98-6.97 (m, 1H), 4.77-4.72 (m, 1H), 4.24-4.20 (m, 1H), 2.61 (s, 3H), 2.21-2.16 (m, 1H), 1.99-1.90 (m, 1H); HPLC purity: 94.55%; HPLC chiral purity: 87.87%;

Synthesis of (3S, 5R)-5-(5-bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-114-ISO-I)

To a stirred solution of Compound 221 (14 g, 39.6 mmol) in DCM (14V, 200 mL) at 0° C. was added DIPEA (21.0 mL, 118.6 mmol), stirred for 15 min, followed by addition of HATU (22.5 g, 59.3 mmol), again stirred for 15 min and then aniline compound (6.3 g, 43.5 mmol) was added. The reaction mixture was then stirred at room temperature for overnight. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was diluted with ice cold water and extracted with DCM. The combined organic layers were dried over anhydrous sodium sulphate and concentrated under reduced pressure to afford a crude compound. The crude compound was purified using silica gel column chromatography to afford HBV-CSU-114-ISO-I (15 g, 79%) as a light brown solid. (see Table 2 for analytical data).

Synthesis of (3S, 5R)—N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-4-yl) thiazol-2-yl)-1, 2, 6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-266-ISO-I)

To a stirring solution of HBV-CSU-114-ISO-I (14 g, 28.9 mmol) in dioxane (11V, 150 mL) was added 1-methyl-4-(tributylstannyl)-1H-imidazole (12.9 g, 34.79 mmol) and purged under Ar atmosphere for 10 min; added Pd(PPh₃)₄ (3.34 g, 2.89 mmol) in a sealed tube; heated to 100° C. and stirred for 4 h. The reaction was monitored by TLC; after completion the reaction the volatiles were removed in vacuo to obtain the crude. The residue obtained was dissolved in 10% MeOH in DCM (35V, 500 mL) and washed with 20% aq. KF (3×200 mL). The organic layer was then dried over anhydrous sodium sulphate, filtered and concentrated to give crude material which was purified through silica gel flash column chromatography using 2% MeOH/CH₂Cl₂ to afford HBV-CSU-266-ISO-I (11.3 g, 80.5%) as an off-white solid (see Table 2 for analytical data).

Scheme 68:

Synthesis of (3S, 5R)—N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-4-yl) thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-276-ISO-I; Resolution of Acid by Cinchonine Approach)

Synthesis of 5-(5-bromothiazol-2-yl)-2-methyl-2H-1,2,6-thiadiazine-3-carboxylic Acid 1,1-dioxide (223)

To a stirring solution of compound 74 (230 g, 606.8 mmol) in CH₃CN: H₂O (1:1, 2300 mL, 10V) was added triethylamine (423 mL, 3034.3 mmol) at 0° C., 15 min, then room temperature for 3.5 h (color change from light yellow to brown was observed after 2 h and then reaction mixture became clear after 1 h). The progress of reaction was monitored by TLC (40% ethyl acetate in hexane). After completion, the reaction mixture was concentrated under reduced pressure; the residue obtained was diluted with water (2 L) and extracted with di-ethyl ether (3×500 mL) (an organic layer showed some compound by LCMS, which was after concentration provided ˜8 g of desired compound with ˜60% LCMS purity). The aqueous layer was acidified with 400 mL of 2N HCl at 0° C. up to pH ˜2-4, precipitated solid was filtered washed with water (200 mL), dried under vacuo to afford Compound 223 (190 g, 88.95%) as a light yellow solid. TLC: 30% EtOAc/hexane (R_f: 0.1); ¹H NMR (DMSO-d₆, 400 MHz): δ 8.30 (s, 1H), 7.21 (s, 1H), 3.59 (s, 3H) (NMR showed some trapped triethyl amine); HPLC purity: 91.45%; LCMS purity: 91.38%; LCMS Calculated for C₈H₆BrN₃O₄S₂: 350.90; LCMS observed: 353.90 (M+2)⁺.

Synthesis of 5-(5-bromothiazol-2-yl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxylic Acid 1,1-dioxide (224)

To a stirred solution of Compound 223 (190 g, 539 mmol) in 2 L of EtOH: THF (10.5V, 3:1) at 0° C. under Ar atmosphere, NaBH₄ (40.83 g, 1079 mmol) was added portion wise and the reaction mixture was stirred at room temperature for 3 h (During addition of NaBH₄, reaction mixture becomes thick). The progress of the reaction was monitored by TLC. After completion, the reaction mixture was concentrated under reduced pressure. The residue obtained was diluted with water (1 L) and extracted with di-ethyl ether (2×200 mL). The organic layer was discarded and aqueous layer was acidified with 200 mL of 4N HCl at 0° C. up to pH ˜4, precipitated solid was filtered washed with water (200 mL), dried under vacuo to afford compound 224 (Cis racemic) (170 g, 88.47%) as an off-white solid. TLC: 15% MeOH/DCM (Rf: 0.2); ¹H NMR (DMSO-d₆, 400 MHz): δ 13.4 (br.s, 1H), 7.88 (s, 1H), 7.82 (d, J=9.6 Hz, 1H), 4.93-4.87 (m, 1H), 4.32-4.28 (m, 1H), 2.63 (s, 3H), 2.37-2.32 (m, 1H), 2.05-1.95 (m, 1H); HPLC purity: 95.57%, LCMS purity: 92.44%; LCMS Calculated for C₈H₁₀BrN₃O₄S₂: 354.93; LCMS observed: 355.95 (M)⁺

Synthesis of 5-(5-bromothiazol-2-yl)-2-methyl-1, 2, 6-thiadiazinane-3-carboxylic Acid 1,1-dioxide (196)

Racemic Compound 224 (190 g, 533.39 mmol) was taken in 5.7 L of IPA (˜30V), to this suspension Cinchonine (157.03 g, 533.39 mmol) was added and the reaction mixture was heated at 90° C. for 2 h (Clear solution was not observed on large scale due to the precipitated solid at the same temperature). The reaction mixture was then allowed to cool down without any agitation to accelerate the crystallization and kept at room temperature for overnight. The crystallized solid was collected by filtration, rinsed with IPA (3×500 mL) to give 210 g of Compound 196-salt (Mother liquor contains 230 g of Compound 225-salt). Both mother liquor and crystals were analyzed by HPLC on chiral amylose SA column (eluent; DCM: MeOH 50:50) analytical samples were prepared by acidification followed by extraction to determine the relative amount of Compound 196-salt and Compound 225-salt. The analysis showed the chiral purity of Compound 196 at 1.18%:98.81% and Compound 225 at 95.5%:4.6%.

The whole batch of Compound 196-salt after IPA wash was taken in 800 mL of ethyl acetate and was acidified at 0° C. to a pH ˜2 to 4 with 4N aq. HCl (420 mL). The organic layer was separated and aqueous layer was further extracted with ethyl acetate (3×250 mL). The combined organic layers were dried over anhydrous sodium sulphate, filtered and concentrated to give 78 g of Compound 196 (chiral purity 98.60%). Similarly 72 g of Compound 225 was obtained (chiral purity 94.71%).

Analytical Data for Compound 196:

¹H NMR (DMSO-d₆, 400 MHz): δ 13.41 (s, 1H), 7.87 (s, 1H), 7.80 (d, J=10.0 Hz, 1H), 4.93-4.86 (m, 1H), 4.30 (dd, J=12.4, 1.8 Hz, 1H), 2.61 (s, 3H), 2.36-2.32 (m, 1H), 2.04-1.95 (m, 1H); HPLC purity: 98.59%; HPLC chiral purity: 98.60%; LCMS purity: 98.60%; LCMS Calculated for C₈H₁₀BrN₃O₄S₂: 354.93; LCMS observed: 357.90 (M+2)⁺.

Analytical Data for Compound 225:

¹H NMR (DMSO-d₆, 400 MHz): 13.41 (s, 1H), δ 7.88 (1H), 7.82 (d, J=9.6 Hz, 1H), 4.94-4.87 (m, 1H), 4.29 (dd, J=12.4, 2.4 Hz, 1H), 2.62 (s, 3H), 2.37-2.33 (m, 1H), 2.04-1.95 (m, 1H); HPLC purity: 91.68%, HPLC chiral purity: 94.71%; LCMS purity: 96.66%; LCMS Calculated for C₈H₁₀BrN₃O₄S₂: 354.93; LCMS observed: 357.6 (M+2)⁺.

Synthesis of (3S, 5R)-5-(5-bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-122-ISO-I)

To a stirred solution of Compound 196 (160 g, 449.4 mmol) in DCM (18V, 2.9 L) at 0° C. was added DIPEA (234.4 mL, 1344.8 mmol), stirred for 30 min, followed by addition of HATU (256.1 g, 674.2 mmol) portion wise, again stirred for 30 min and then aniline compound (78.2 g, 539.3 mmol) was added. The reaction mixture was then stirred at room temperature for overnight. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was concentrated, the residue obtained was stirred with ethyl acetate (500 mL) for 30 min, solid material (Tetramethyl urea side product and HOBT) obtained was filtered, washed with 200 mL ethyl acetate. The filtrate was washed with water (2×200 mL) followed by brine (2×200 mL), the organic layer was dried over anhydrous sodium sulphate, filtered and concentrated under reduced pressure to afford a crude compound (60% purity by LCMS). The crude material was stirred with DCM (5V, 800 mL), the precipitated solid was filtered, washed with DCM (2V, 300 mL) and dried to afford 146 g (67.4%) of HBV-CSU-122-ISO-I; TLC: 30% EtOAc/Hexane (R_f: 0.5) (see Table 2 for analytical data).

Synthesis of (3S, 5R)—N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-4-yl) thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-276-ISO-I)

To a stirring solution of HBV-CSU-122-ISO-I (72.5 g, 150.4 mmol) in 1,4-dioxane (730 mL) was added 1-methyl-4-(tributylstannyl)-1H-imidazole (83.8 g, 225.6 mmol) and purged under Ar atmosphere for 30 min; added Pd(PPh₃)₄ (17.37 g, 15.04 mmol); heated to 100° C. and stirred for 4 h at the same temperature. The reaction mixture was monitored by TLC. After completion, the reaction mixture was filtered through a pad of a Celite, washed with ethyl acetate (2×500 mL), combined filtrate was concentrated and solid residue obtained was triturated with ether (2×500 mL) and ether layer was concentrated (ether layer showed stannane as well as some compound by TLC). The solid residue was again stirred with ˜500 mL hexane (hexane layer showed some stannane by TLC; this hexane layer was combined for concentration with ether layer). The residue obtained after ether/hexane washings were dissolved in 1 Lit of ethyl acetate; washed with 30% aq. KF (5×500 mL) followed by brine (500 mL). The combined organic layer was dried over anhydrous sodium sulphate, filtered and concentrated in vacuo to afford the crude material which was purified using silica gel flash column chromatography (2-4% MeOH/CH₂Cl₂). {Note: One more batch done on same scale (72.5 g)}. The combined work-up and purification provided HBV-CSU-276-ISO-I (110 g, 75.5%) as an off-white solid. TLC: 10% MeOH/CH₂Cl₂ (R_f: 0.2); ¹H NMR showed some stannane related impurities. In order to get rid of stannane impurity, 110 g of HBV-CSU-276-ISO-I was stirred with ether (500 mL) for 30 min, filtered, washed with ether (2×100 mL) and dried to provide 108 g (74.17%) of HBV-CSU-276-ISO-I (see Table 2 for analytical data).

HCl Salt Formation:

To a solution of HBV-CSU-276-ISO-I (62 g) in 620 mL of Dioxane: MeOH (1:1) at 0° C. (clear solution was observed) was added 160 mL of 4M HCl in MeOH (5 eq.), the reaction mixture was stirred at 0° C. for 1 h (We did observed the solid precipitating out at 0° C. after 5 minutes). The precipitated solid was collected by filtration, washed with ether (3×100 mL) followed by pentane (3×100 mL) via stirring & dried to afford 63 g of HBV-CSU-276-ISO-I-HCl salt. The ¹H NMR showed ˜4.66% w/w methanol; (see Table 2 for analytical data).

Scheme 69:

Synthesis of (3R, 5R)-5-(5-bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-114-Trans-ISO-I) and (3R, 5R)—N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-266-Trans-ISO-I)

Synthesis of (3R, 5R)-5-(5-bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-114-Trans-ISO-I)

To a stirred solution of compound HBV-CSU-114-Cis-ISO-I (3 g, 6.20 mmol) in 1,4-dioxane (30 mL), Na₂CO₃ (3.28 g, 31 mmol) was added. The reaction mixture was stirred at 100° C. for 16 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was concentrated under reduced pressure. The residue was diluted with water and extracted with ethyl acetate. The combined organic layers were dried over anhydrous sodium sulphate and concentrated under reduced pressure to afford a crude compound. The crude compound was purified using silica gel column chromatography to afford HBV-CSU-114-Trans-ISO-I (0.05 g, 2%) (see Table 2 for analytical data).

(3R, 5R)—N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-266-Trans-ISO-I)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-114-Trans-ISO-I and corresponding stannane (see Table 2 for analytical data).

Scheme 70:

Synthesis of (3S, 5S)-5-(5-bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-114-Trans-ISO-II) and (3S, 5S)—N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-266-Trans-ISO-II)

Synthesis of (3S, 5S)-5-(5-bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-114-Trans-ISO-II)

To a stirred solution of compound HBV-CSU-114-Cis-ISO-II (0.2 g, 0.413 mmol) in 1,4-dioxane (10 mL), Na₂CO₃ (0.22 g, 2.07 mmol) was added. The reaction mixture was stirred at 100° C. for 16 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was concentrated under reduced pressure. The residue was diluted with water and extracted with ethyl acetate. The combined organic layers were dried over anhydrous sodium sulphate, filtered and concentrated under reduced pressure to afford a crude compound. The crude compound was purified using silica gel column chromatography to afford HBV-CSU-114-Trans-ISO-II (0.02 g, 10%) (see Table 2 for analytical data).

(3S, 5S)—N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-266-Trans-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-114-Trans-ISO-II and corresponding stannane (see Table 2 for analytical data).

Scheme 71:

Synthesis of (3R,5R)-5-(5-bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-122-Trans-ISO-I) and (3R, 5R)—N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-276-Trans-ISO-I)

Synthesis of (3R, 5R)-5-(5-bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-122-Trans-ISO-I)

To a stirred solution of compound HBV-CSU-122-ISO-I (0.2 g, 0.413 mmol) in 1,4-dioxane (5 mL), Na₂CO₃ (0.218 g, 2.066 mmol) was added. The reaction mixture was stirred at 100° C. for 16 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was concentrated under reduced pressure. The residue was diluted with water and extracted with ethyl acetate. The combined organic layers were dried over anhydrous sodium sulphate and concentrated under reduced pressure to afford a crude compound. The crude compound was purified using silica gel column chromatography to afford HBV-CSU-122-Trans-ISO-I (0.02 g, 10%) (see Table 2 for analytical data).

(3R, 5R)—N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-276-Trans-ISO-I)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-122-Trans-ISO-I and corresponding stannane (see Table 2 for analytical data).

Scheme 72:

Synthesis of (3S,5S)-5-(5-bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-122-Trans-ISO-II) and (3S, 5S)—N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-276-Trans-ISO-II)

Synthesis of (3S, 5S)-5-(5-bromothiazol-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-122-Trans-ISO-II)

To a stirred solution of compound HBV-CSU-122-ISO-II (0.99 g, 2.06 mmol) in 1,4-dioxane (10 mL), Na₂CO₃ (1.09 g, 10.37 mmol) was added. The reaction mixture was stirred at 100° C. for 16 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was concentrated under reduced pressure. The residue was diluted with water and extracted with ethyl acetate. The combined organic layers were dried over anhydrous sodium sulphate and concentrated under reduced pressure to afford a crude compound. The crude compound was purified using silica gel column chromatography to afford HBV-CSU-122-Trans-ISO-II (0.07 g, 7%) (see Table 2 for analytical data).

(see Table 2 for analytical data).

(3S, 5S)—N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-imidazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-276-Trans-ISO-II)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-122-Trans-ISO-II and corresponding stannane (see Table 2 for analytical data).

Scheme 73:

Synthesis of Trans-5-(5-bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-114-Trans {Rac}) & Trans-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-161-Trans {Rac})

Synthesis of Trans-5-(5-bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-114-Trans {Rac})

To a stirred solution of compound CSU-114_amide (10 g, 20.87 mmol) and {Noyori (S, 5) catalyst} i.e. RuCl [(1S, 2S)-p-TsNCH (C₆H₅) NH₂] (η6-p-cycmene) (5.64 mL, 2.08 mmol) in DCM (100 mL) at 0° C., DIPEA (7.2 mL, 41.74 mmol) and formic acid (4.8 g, 104.35 mmol) were added The reaction mixture was stirred at room temperature for 16 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was diluted with water and extracted with DCM. The combined organic layers were dried over anhydrous sodium sulphate and concentrated under reduced pressure to afford a crude compound. The crude compound was purified by silica gel column chromatography to afford the desired compound as HBV-CSU-114-Trans (Rac) (2.6 g, 26%) (see Table 2 for analytical data). Note: The Cis isomer was also observed which was separated by column chromatography. The stereochemistry at C-3 was not confirmed and assigned based on an outcome of fully reduced cis product after 16 h.

Synthesis of Trans-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-161-Trans {Rac})

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-114-Trans (Rac) and 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (see Table 2 for analytical data).

Scheme 74:

Synthesis of Amides Using 2-methyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxylic Acid 1,1-dioxide

Target R variation
HBV-CSU-411
HBV-CSU-413
HBV-CSU-415
HBV-CSU-416
HBV-CSU-425

Synthesis of 2-methyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxylic Acid 1,1-dioxide (226)

To a mixture of bromo Compound 220 (500 mg, 1.41 mmol), boronic acid/boronate ester (293 mg, 1.41 mmol) in 5 mL of 1,4-dioxane:H₂O (1:1), DIPEA (0.7 mL, 4.2 mmol) was added, purged with Ar for 15 min, followed by the addition of PdCl₂(PPh₃)₂ (9 mg, 0.0141 mmol), and stirred at 80° C. for overnight. The progress of the reaction was monitored by LCMS. After completion of the reaction, the reaction mixture was filtered through Celite and evaporated to dryness. The residue was taken in water and acidified with 2N HCl (2-4 pH), precipitated solid was filtered and dried to afford Compound 226 (400 mg, 79%) as a light yellow solid. LCMS Calculated for C₁₃H₁₆N₄O₄S₂: 356.06; LCMS observed: 357.6 (M+1)⁺.

Synthesis of Cis-2-methyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-N-(3,4,5-trifluorophenyl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-411)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using Compound 226 and corresponding amine (see Table 2 for analytical data).

Synthesis of Cis-N-(3,4-difluorophenyl)-2-methyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-413)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using Compound 226 and corresponding amine (see Table 2 for analytical data).

Synthesis of Cis-N-(3-cyclopropyl-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-415)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using Compound 226 and corresponding amine (see Table 2 for analytical data).

Synthesis of Cis-N-(3-cyano-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-416)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using Compound 226 and corresponding amine (see Table 2 for analytical data).

Synthesis of Cis-2-methyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-N-(pyridin-3-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-425)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using Compound 226 and corresponding amine (see Table 2 for analytical data).

Scheme 75:

Synthesis of Rac-5-(5-bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2,4-dimethyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide ((HBV-CSU-423) & Rac-N-(3-chloro-4-fluorophenyl)-2,4-dimethyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-343)

Synthesis 1-(5-bromothiophen-2-yl)propan-1-one (227)

To a stirred solution of AlCl₃ (29.44 g, 221 mmol) in EDC (300 mL) at 0° C., propionyl chloride (17.02 g, 184 mmol) was added and reaction mixture was stirred for 20 min at 0° C. To this solution, compound 231 (30 g, 184 mmol) was added and further stirred at room temperature for overnight. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was diluted with water and extracted with DCM. The combined organic layers were dried over anhydrous sodium sulphate, filtered and concentrated under reduced pressure to afford the title compound 227 (38.20 g, 95%) as brown coloured solid; TLC: 20% EtOAc/hexane (R_f: 0.4); ¹H NMR (400 MHz, DMSO-d₆): δ 7.79 (d, J=4.4 Hz, 1H), 7.38 (d, J=4.0 Hz, 1H), 2.97-2.92 (m, 2H), 1.07 (t, J=7.2 Hz, 3H); LCMS Calculated for C₇H₇BrOS: 217.94; Observed: 220.80 (M+2)⁺.

Synthesis of Methyl 4-(5-bromothiophen-2-yl)-3-methyl-2,4-dioxobutanoate (228)

Title compound was synthesized using general method for the synthesis of 2, 4-diketoester described above to afford 12.5 g of compound 228 (45%, reaction scale is 20 g) as an off white solid. TLC: 30% EtOAc/hexane (R_f: 0.3); LCMS Calculated for C₁₀H₉BrO₄S: 303.94; Observed: 304.95 (M+1)⁺.

Synthesis of Methyl 5-(5-bromothiophen-2-yl)-4-methyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (229)

Title compound was synthesized using general method B for the synthesis of cyclic sulfonamide described above to afford 1.7 g of compound 229 (18%, reaction scale is 8 g) as an off white solid. TLC: 5% MeOH/DCM (R_f: 0.3); LCMS Calculated for C₁₀H₉BrN₂O₄S₂: 363.92; LCMS observed: 366.95 (M+2)⁺.

Synthesis of Methyl 5-(5-bromothiophen-2-yl)-2,4-dimethyl-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (230)

Title compound was synthesized using general method A for alkylation described above to afford 0.32 g of compound 230 (62%, reaction scale is 1 g) as an off white solid. TLC: 30% EtOAc/hexanes (R_f: 0.2); LCMS Calculated for C₁₁H_nBrN₂O₄S₂: 377.93; LCMS observed: 380.8 (M+2)⁺.

Synthesis of 5-(5-Bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2,4-dimethyl-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-423-Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using Compound 230 and corresponding amine (see Table 1 for analytical data).

Synthesis of Rac-5-(5-bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2,4-dimethyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-423)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-423_Int (see Table 2 for analytical data).

Note: NMR hints for three Diastereomers.

Synthesis of Rac-N-(3-chloro-4-fluorophenyl)-2,4-dimethyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-343)

To a mixture of HBV-CSU-423 (250 mg, 0.502 mmol), corresponding boronic acid/boronate ester (104 mg, 0.502 mmol) in 5 mL of 1,4-dioxane:H₂O (1:1), DIPEA (0.129 g, 1.00 mmol) was added, purged with Ar for 15 min, followed by the addition of PdCl₂(PPh₃)₂ (4 mg, 0.005 mmol), and stirred at 80° C. for overnight. The progress of the reaction was monitored by LCMS. After completion of the reaction, the reaction mixture was diluted with water and extracted using ethyl acetate. The combined organic layers were dried over anhydrous sodium sulphate, filtered and concentrated under reduced pressure to provide crude compound. The crude compound was purified by prep. HPLC to afford the title compound. HBV-CSU-343 (42 mg, 17%). (see Table 2 for analytical data).

Note: NMR hints for three Diastereomers.

Scheme 76:

Synthesis of 5-(5-Bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-3,4-dihydro-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-367) & Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-3,4-dihydro-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-429)

Cis-5-(5-Bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2-methyl-3,4-dihydro-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-367)

To a stirred solution of compound HBV-CSU-114-Int (1 g, 2.08 mmol) in DCM at 0° C., was added formic acid (0.48 g, 10.44 mmol) followed by DIPEA (0.538 g, 4.17 mmol) and then Noyori catalyst (0.132 g, 0.208 mmol). The reaction mixture was warmed to room temperature, the turbid solution was stirred at the same temperature for 50 min (till to get red colored clear solution). The progress of the reaction was monitored by TLC. After completion, the reaction mixture was concentrated under reduced pressure (at 30° C.). The crude compound was purified by silica gel column chromatography to afford the title compound HBV-CSU-367 (see Table 2 for analytical data).

Cis-N-(3-chloro-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-3,4-dihydro-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-429)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-367 and corresponding stannane (see Table 2 for analytical data).

Scheme 77:

Synthesis of Cis-2-allyl-5-(5-bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-391), Cis-2-allyl-N-(3-chloro-4-fluorophenyl)-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-394), Cis-2-allyl-N-(3-chloro-4-fluorophenyl)-5-(5-(1-methyl-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-395), Cis-2-allyl-N-(3-chloro-4-fluorophenyl)-5-(5-(pyridin-2-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-396), Cis-N-(3-chloro-4-fluorophenyl)-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-427) &

Synthesis of Methyl 2-allyl-5-(5-bromothiophen-2-yl)-2H-1,2,6-thiadiazine-3-carboxylate 1,1-dioxide (232)

To a stirred solution of compound HBV-CSU-114-Int (10 g, 28.40 mmol) in dry DMF (100 mL) at 0° C. under Ar atmosphere, NaH (60% w/w in mineral oil, 1.49 g, 62.4 mmol) was added and stirred at 0° C. for 30 min. To this solution, 3-iodoprop-1-ene (5.6 g, 33.89 mmol) was added slowly and resulting reaction mixture was stirred at room temperature for 16 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was diluted with ice cold water and extracted with ethyl acetate. The combined organic layers were washed with water, brine, dried over anhydrous sodium sulfate and evaporated under reduced pressure. The crude compound was purified by silica gel column chromatography using 10% EtOAC/hexane to afford the title compound 232 (3.8 g, 34.38%) as a colorless oil. TLC: 30% EtOAc/hexanes (R_f: 0.5); LCMS Calculated for C₁₂H₁₁BrN₂O₄S₂: 389.93; LCMS observed: 392.90 (M+2)⁺.

Synthesis of 2-allyl-5-(5-bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-391-Int)

The above titled compound has been synthesized by following the general procedure (Method A) described above for amidation by using Compound 232 and corresponding amine (see Table 1 for analytical data).

Synthesis of Cis-2-allyl-5-(5-bromothiophen-2-yl)-N-(3-chloro-4-fluorophenyl)-2H-1,2,6-thiadiazine-3-carboxamide 1,1-dioxide (HBV-CSU-391)

The above titled compounds have been synthesized by following the general procedure described above for reduction by using corresponding HBV-CSU-391_Int (see Table 2 for analytical data).

Synthesis of Cis-2-allyl-N-(3-chloro-4-fluorophenyl)-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-394)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-391 and corresponding boronic acid (see Table 2 for analytical data).

Synthesis of Cis-2-allyl-N-(3-chloro-4-fluorophenyl)-5-(5-(1-methyl-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-395)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-391 and corresponding stannane (see Table 2 for analytical data).

Synthesis of Cis-2-allyl-N-(3-chloro-4-fluorophenyl)-5-(5-(pyridin-2-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-396)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-391 and corresponding stannane (see Table 2 for analytical data).

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-427)

The above titled compounds have been synthesized by following the general procedure described above for Suzuki coupling by using HBV-CSU-391 and corresponding boronic acid (see Table 2 for analytical data).

Note: This compound was obtained as a side product.

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-5-(5-(1-methyl-1H-imidazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-428)

The above titled compounds have been synthesized by following the general procedure described above for Stille coupling by using HBV-CSU-391 and corresponding stannane (see Table 2 for analytical data).

Note: This compound was obtained as a side product.

Scheme 78:

Synthesis of amides using 2-methyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-1,2,6-thiadiazinane-3-carboxylic Acid 1,1-dioxide

Target R variation
HBV-CSU-421
HBV-CSU-422

Synthesis of 2-methyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxylic acid 1,1-dioxide (233)

To a mixture of bromo Compound 224 (500 mg, 1.41 mmol), boronic acid/boronate ester (321 mg, 1.54 mmol) in 4 mL of 1,4-dioxane:H₂O (1:1), DIPEA (543 mg, 4.21 mmol) was added, purged with Ar for 15 min, followed by the addition of PdCl₂(PPh₃)₂ (10 mg, 0.0140 mmol), and stirred at 80° C. for overnight. The progress of the reaction was monitored by LCMS. After completion of the reaction, the reaction mixture was filtered through Celite and evaporated to dryness. The residue was taken in water and acidified with 2N HCl (2-4 pH), precipitated solid was filtered and dried to afford Compound 233 (400 mg, 80%) as a light yellow solid. LCMS Calculated for C₁₂H₁₅N₅O₄S₂: 357.06; LCMS observed: 358.05 (M+1)⁺.

Synthesis of Cis-N-(3-cyclopropyl-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-421)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using Compound 233 and corresponding amine (see Table 2 for analytical data).

Synthesis of Cis-N-(3-cyano-4-fluorophenyl)-2-methyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiazol-2-yl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-422)

The above titled compound has been synthesized by following the general procedure (Method B) described above for amidation by using Compound 233 and corresponding amine (see Table 2 for analytical data).

Scheme 79:

Synthesis of Amides Using 5-(5-bromothiazol-2-yl)-2-methyl-1,2,6-thiadiazinane-3-carboxylic Acid 1,1-dioxide Followed by C-C Coupling

Target R variation
HBV-CSU-417

To a stirred solution of above acid compound (1 eq.) in DCM/DMF (10V) at 0° C. was added DIPEA (3 eq.), stirred for 15 min, followed by addition of HATU (1.5 eq.), again stirred for 15 min and then corresponding aniline (1.2 eq.) was added. The reaction mixture was then stirred at room temperature for overnight. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was diluted with ice cold water and extracted with DCM. The combined organic layers were dried over anhydrous sodium sulphate and concentrated under reduced pressure to afford a crude compound. The crude compound was taken in methanol (10V), stirred for 15 min., filtered and dried under reduced pressure to afford compound desired compound. LCMS Calculated for C₁₄H₁₂BrF₃N₄O₃S₂: 483.95; LCMS observed: 485.95 (M+2)⁺.

Synthesis of Cis-2-methyl-5-(5-(1-methyl-1H-pyrazol-4-yl)thiazol-2-yl)-N-(3,4,5-trifluorophenyl)-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-417)

To a mixture of corresponding bromo compound for HBV-CSU-417 (1 eq), boronic acid/boronate ester (1.2 eq) in 1,4-dioxane:H₂O (1:1), DIPEA (2 eq) was added, purged with Ar gas for 15 min, followed by the addition of PdCl₂(PPh₃)₂ (0.005 eq), and stirred at 80° C. for overnight. The progress of the reaction was monitored by LCMS. After completion of the reaction, the reaction mixture was diluted with water and extracted with ethyl acetate. The combined organic layers were dried over anhydrous sodium sulphate and concentrated under reduced pressure. The crude compound was purified by silica gel column chromatography to afford title compound HBV-CSU-417 (see Table 2 for analytical data).

Scheme 80:

Synthesis of Cis-N-(3-chloro-4-fluorophenyl)-5-(5-(1-methyl-1H-pyrazol-4-yl)thiophen-2-yl)-2-propyl-1,2,6-thiadiazinane-3-carboxamide 1,1-dioxide (HBV-CSU-424)

To a stirred solution of compound HBV-CSU-394 (0.035 g, 0.068 mmol) in ethanol (5 mL), 10% Pd/C (10% w/w) of substrate, 3 mg) was added and the reaction mixture was stirred under hydrogen atmosphere (balloon pressure) at room temperature for 16 h. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was filtered through a pad of celite, the filtrate was evaporated under reduced pressure and the resulting residue was triturated with diethyl ether and n-pentane to afford the title compound HBV-CSU-424 (see Table 2 for analytical data).

Lengthy table referenced here
US20230012463A1-20230112-T00001
Please refer to the end of the specification for access instructions.

Lengthy table referenced here
US20230012463A1-20230112-T00002
Please refer to the end of the specification for access instructions.

Stereochemistry of the Examples:

The Crystal structure of HBV-CSU-016-ISO-I is shown in FIG. 1. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii. Dashed line indicates hydrogen bond. The Crystal data and structure refinement for HBV-CSU-016-ISO-1 are as follows:

Identification code	SAP-MA1703-08(isomer-1)
	(IICT file code: KA84_0m)
Empirical formula	C15H15BrF N3O3S2
Formula weight	448.33
Temperature	100(2) K
Wavelength	0.71073 Å
Crystal system	Monoclinic
Space group	P21
Unit cell dimensions	a = 5.001(6) Å	α = 90°.
	b = 25.63(3) Å	β = 94.240(19)°.
	c = 13.390(16) Å	γ = 90°.
Volume	1712(4) Å3
Z	4
Density (calculated)	1.740 Mg/m3
Absorption coefficient	2.676 mm−1
F(000)	904
Crystal size	0.310 × 0.240 × 0.190 mm3
θ range for data collection	2.830 to 28.374°.
Index ranges	−6 <= h <= 6, −34 <= k <=
	34, −17 <= l <= 17
Reflections collected	50333
hidependent reflections	8467 [R(int) = 0.0361]
Completeness to θ = 25.242°	99.8%
Refinement method	Full-matrix least-squares on F2
Data/restraints/parameters	8467/1/469
Goodness-of-fit on F2	1.022
Final R indices [I > 2σ(I)]	R1 = 0.0265, wR2 = 0.0596
R indices (all data)	R1 = 0.0313, wR2 = 0.0610
Absolute structure parameter	0.034(2)
Largest diff. peak and hole	0.311 and −0.513 e.A−3
Measurement	Bruker D8 QUEST PHOTON-100
	Detector
Software Used	SHELXTL-PLUS

The absolute stereochemistry at each chiral center was assigned using the PLATON computer application as described by A. L. Spek in J. APPL. CRYST. 36, 7-13, 2003. The designated chiral centers are:

• • C(1A) Chiral: R
  • C(1B) Chiral: R
  • C(3A) Chiral: S
  • C(3B) Chiral: S

The absolute stereochemistry of all other sets of enantiomers were assigned based on this crystal structure determination. In each case only one of the stereoisomers of the pair had significant activity and the active isomer was assigned the same stereochemistry as HBV-CSU-016-ISO-I.

Assay Measuring Activity of Test Compounds on Viral Production from HepAD38 Cells

HepAD38 cells grown in a T-150 flask (Corning, cat #: 430825) with Growth Medium (DMEM/F12 (1:1) (Hyclone, cat #: SH30023.02), 1× Pen/Strep (Invitrogen, cat #: 15140-122), 10% FBS (Tissue Culture Biologics, cat #: 101), 250 μg/mL G418 (Alfa Aesar, cat #: J62671), 1 μg/mL Tetracycline (Teknova, cat #: T3320)) were detached with 0.25% trypsin-EDTA (Invitrogen, cat #: 25200-056). Tetracycline-free treatment medium (15 mL DMEM/F12 (1:1) 1× Pen/step, with 2% FBS, Tet-system approved (Clontech, cat #: 631106) were then added to mix, transferred into a 50 ml conical tube (Falcon, cat #: 21008-918,) and spun at 1300 rpm for 5 min. Pelleted cells were then re-suspended/washed with 50 mL of 1×DPBS (Invitrogen, cat #: 14190-136) 2 times and 50 mL treatment medium twice. HepAD38 cells were then re-suspended with 10 mL of treatment medium, syringed and counted. Wells of 96-well clear bottom TC plate (Corning, cat #: 3904,) were seeded at 50,000 cells/well in 180 μL of treatment medium, and 20 μL of either 10% DMSO (Sigma, cat #: D4540) as controls or a 10× solution of test compounds in 10% DMSO in treatment media was added for a final compound concentration starting at 10 μM, and plates were incubated in 5% CO₂ incubator at 37° C. for 5 days.

Subsequently viral load production was assayed by quantitative PCR (qPCR) of the HBV core sequence. PCR reaction mixture containing forward primers HBV-f 5′-CTGTGCCTTGGGTGGCTTT-3′, which is SEQ ID NO 1, (IDT DNA), Reverse primers HBV-r 5′-AAGGAAAGAAGTCAGAAGGCAAAA-3′, which is SEQ ID NO 2 (IDT DNA), Fluorescent TaqMan™ Probes HBV-probe 5′-FAM/AGCTCCAAA/ZEN/TTCTTTATAAGGGTCGATGTC/3IABkFQ-3′ (IDT DNA), which is SEQ ID NO 3, 10 μL/well of PerfeCTa® qPCR ToughMix® (Quanta Biosciences, Cat #: 95114-05K), and 6 μL/well of DEPC water (Alfa Aesar, cat #: J62087) was prepared. Four μL of supernatant was added to 16 μL of the reaction mixture in a qPCR plate (Applied Biosystems, Cat #: 4309849), sealed with a film (Applied Biosystems, Cat #: 4311971), centrifuged for a few seconds, and subsequently run on an Applied Biosystems VIIA7. The PCR mixture was incubated at 45° C. for 5 min, then 95° C. for 10 min, followed by 40 cycles of 10 seconds at 95° C. and 20 seconds at 60° C. Viral load was quantified against known HBV DNA standards by using ViiA™ 7 Software. Viral load in the supernatant from wells with treated cells were compared against viral load in supernatant from DMSO control wells (>3 per plate). Cell viability assay was performed with CellTiter-Glo Luminescent Cell Viability Assay (Promega, cat #: G7573) with modification. Mixed appropriate amount of CellTiter-Glo (CTG) 1×DPBS in a 1:1 ratio, added 100 uL of the mixture to each well followed completely removal of all supernatant in each well without touching cell surface. Incubated the plate at room temperature for 10 min on an orbital shaker, and then read the plate with a plate reader (TECAN M1000 or Envision). EC₅₀ or CC₅₀ values were calculated through curve-fitting of the four-parameter nonlinear-logistic-regression model (GraphPad Prism or Dotmatics). CC₅₀ values were all >10 μM.

Table 3 gives the viral load lowering EC₅₀ values grouped in the following ranges: A indicates EC₅₀<1 μM; B indicates EC₅₀ 1-5 μM; C indicates EC₅₀>5 μM.

TABLE 3
Compound                 Viral Load EC50 Activity range
HBV-CSU-006              A
HBV-CSU-007              A
HBV-CSU-010              A
HBV-CSU-010- ISO-I       A
HBV-CSU-011              A
HBV-CSU-012              B
HBV-CSU-013              A
HBV-CSU-014              B
HBV-CSU-015              B
HBV-CSU-016              A
HBV-CSU-016- ISO-I       A
HBV-CSU-017              A
HBV-CSU-017- ISO-I       A
HBV-CSU-018              B
HBV-CSU-019              C
HBV-CSU-020              A
HBV-CSU-020- ISO-I       A
HBV-CSU-023              B
HBV-CSU-024              A
HBV-CSU-025              A
HBV-CSU-025- ISO-I       C
HBV-CSU-025- ISO-II      A
HBV-CSU-027              A
HBV-CSU-027- ISO-I       C
HBV-CSU-029- ISO-I       A
HBV-CSU-031              A
HBV-CSU-031- ISO-I       A
HBV-CSU-031- ISO-II      C
HBV-CSU-032              A
HBV-CSU-032- ISO-I       A
HBV-CSU-032- ISO-II      C
HBV-CSU-033              A
HBV-CSU-036              A
HBV-CSU-040              A
HBV-CSU-041              C
HBV-CSU-043- ISO-I       C
HBV-CSU-043- ISO-II      C
HBV-CSU-044- ISO-II      C
HBV-CSU-044-ISO-I        C
HBV-CSU-045              A
HBV-CSU-045- ISO-I       A
HBV-CSU-046- ISO-I       A
HBV-CSU-047- ISO-I       A
HBV-CSU-048- ISO-I       A
HBV-CSU-049- ISO-I       A
HBV-CSU-050- ISO-I       B
HBV-CSU-050- ISO-II      C
HBV-CSU-054- ISO-I       C
HBV-CSU-054- ISO-II      B
HBV-CSU-055- ISO-I       A
HBV-CSU-055- ISO-II      C
HBV-CSU-056- ISO-I       A
HBV-CSU-056- ISO-II      C
HBV-CSU-057              A
HBV-CSU-058              A
HBV-CSU-058- ISO-I       C
HBV-CSU-058- ISO-II      A
HBV-CSU-059              A
HBV-CSU-059- ISO-I       C
HBV-CSU-059- ISO-II      A
HBV-CSU-060- ISO-I       C
HBV-CSU-060- ISO-II      A
HBV-CSU-064              C
HBV-CSU-071              B
HBV-CSU-071- ISO-I       A
HBV-CSU-071- ISO-II      B
HBV-CSU-072              A
HBV-CSU-072- ISO-I       C
HBV-CSU-072- ISO-II      A
HBV-CSU-073              C
HBV-CSU-074              C
HBV-CSU-077- ISO-I       C
HBV-CSU-077- ISO-II      A
HBV-CSU-078              B
HBV-CSU-078- ISO-I       A
HBV-CSU-078- ISO-II      C
HBV-CSU-079-Rac-A        A
HBV-CSU-079-Rac-B        A
HBV-CSU-082              C
HBV-CSU-083              C
HBV-CSU-083- ISO-I       C
HBV-CSU-083- ISO-II      C
HBV-CSU-089- ISO-I       A
HBV-CSU-089- ISO-II      C
HBV-CSU-090              A
HBV-CSU-090- ISO-I       A
HBV-CSU-090- ISO-II      C
HBV-CSU-092              B
HBV-CSU-092- ISO-I       A
HBV-CSU-092- ISO-II      C
HBV-CSU-093              C
HBV-CSU-093- ISO-I       B
HBV-CSU-093- ISO-II      C
HBV-CSU-094- ISO-I       C
HBV-CSU-094- ISO-II      A
HBV-CSU-095              B
HBV-CSU-095- ISO-I       B
HBV-CSU-095- ISO-II      B
HBV-CSU-096              B
HBV-CSU-096- ISO-I       C
HBV-CSU-096- ISO-II      A
HBV-CSU-097              C
HBV-CSU-097- ISO-I       C
HBV-CSU-097- ISO-II      C
HBV-CSU-101- ISO-I       C
HBV-CSU-101- ISO-II      C
HBV-CSU-102              C
HBV-CSU-102- ISO-I       C
HBV-CSU-102- ISO-II      C
HBV-CSU-103              C
HBV-CSU-103- ISO-I       C
HBV-CSU-103- ISO-II      B
HBV-CSU-108              C
HBV-CSU-109              A
HBV-CSU-109- ISO-I       C
HBV-CSU-109- ISO-II      A
HBV-CSU-110              C
HBV-CSU-111              B
HBV-CSU-112 (Cis)        A
HBV-CSU-112- ISO-I       A
HBV-CSU-112- ISO-II      C
HBV-CSU-113- ISO-I       A
HBV-CSU-113- ISO-II      C
HBV-CSU-114              A
HBV-CSU-114- ISO-I       A
HBV-CSU-114- ISO-II      C
HBV-CSU-114-Trans (Rac)  C
HBV-CSU-114-Trans-ISO-I  B
HBV-CSU-114-Trans-ISO-II B
HBV-CSU-115              A
HBV-CSU-115- ISO-I       A
HBV-CSU-115- ISO-II      C
HBV-CSU-116- ISO-I       A
HBV-CSU-116- ISO-II      B
HBV-CSU-117              A
HBV-CSU-117- ISO-I       A
HBV-CSU-117- ISO-II      B
HBV-CSU-120              A
HBV-CSU-122              A
HBV-CSU-122- ISO-I       A
HBV-CSU-122- ISO-II      B
HBV-CSU-122-Trans-ISO-I  B
HBV-CSU-122-Trans-ISO-II B
HBV-CSU-123              A
HBV-CSU-123- ISO-I       A
HBV-CSU-123- ISO-II      C
HBV-CSU-124              A
HBV-CSU-124-ISO-I        A
HBV-CSU-124-ISO-II       B
HBV-CSU-142              A
HBV-CSU-142- ISO-I       B
HBV-CSU-142- ISO-II      A
HBV-CSU-143              A
HBV-CSU-146              A
HBV-CSU-146- ISO-I       A
HBV-CSU-146- ISO-II      C
HBV-CSU-147              A
HBV-CSU-147- ISO-I       A
HBV-CSU-147- ISO-II      C
HBV-CSU-148- ISO-I       A
HBV-CSU-148- ISO-II      B
HBV-CSU-149- ISO-I       A
HBV-CSU-149- ISO-II      B
HBV-CSU-150              A
HBV-CSU-156              A
HBV-CSU-156- ISO-I       A
HBV-CSU-156- ISO-II      C
HBV-CSU-157              B
HBV-CSU-158              B
HBV-CSU-158- ISO-I       A
HBV-CSU-158- ISO-II      C
HBV-CSU-159              A
HBV-CSU-159- ISO-I       B
HBV-CSU-159- ISO-II      A
HBV-CSU-160              A
HBV-CSU-160- ISO-I       A
HBV-CSU-160- ISO-II      B
HBV-CSU-161              A
HBV-CSU-161- ISO-I       A
HBV-CSU-161- ISO-II      B
HBV-CSU-161-Trans (Rac)  B
HBV-CSU-162              A
HBV-CSU-162- ISO-I       A
HBV-CSU-162- ISO-II      B
HBV-CSU-163              A
HBV-CSU-163- ISO-I       A
HBV-CSU-163- ISO-II      A
HBV-CSU-164              A
HBV-CSU-164- ISO-I       A
HBV-CSU-164- ISO-II      C
HBV-CSU-165              B
HBV-CSU-166              A
HBV-CSU-166- ISO-I       A
HBV-CSU-166- ISO-II      C
HBV-CSU-167- ISO-I       A
HBV-CSU-167- ISO-II      C
HBV-CSU-168              A
HBV-CSU-168- ISO-I       B
HBV-CSU-168- ISO-II      A
HBV-CSU-169- ISO-I       A
HBV-CSU-169- ISO-II      B
HBV-CSU-170              A
HBV-CSU-170- ISO-I       A
HBV-CSU-170- ISO-II      A
HBV-CSU-171              A
HBV-CSU-171- ISO-I       A
HBV-CSU-173              A
HBV-CSU-173- ISO-I       A
HBV-CSU-173- ISO-II      C
HBV-CSU-175              A
HBV-CSU-175- ISO-I       A
HBV-CSU-175- ISO-II      A
HBV-CSU-176              A
HBV-CSU-176- ISO-I       A
HBV-CSU-176- ISO-II      C
HBV-CSU-177              A
HBV-CSU-177- ISO-I       A
HBV-CSU-178              A
HBV-CSU-178-ISO-I        A
HBV-CSU-178-ISO-II       B
HBV-CSU-179              A
HBV-CSU-179-ISO-I        A
HBV-CSU-179-ISO-II       B
HBV-CSU-188              A
HBV-CSU-200              A
HBV-CSU-201              A
HBV-CSU-202              A
HBV-CSU-204              A
HBV-CSU-205              A
HBV-CSU-208              A
HBV-CSU-208- ISO-I       C
HBV-CSU-208- ISO-II      A
HBV-CSU-209              A
HBV-CSU-210              A
HBV-CSU-210- ISO-I       C
HBV-CSU-210- ISO-II      A
HBV-CSU-211              A
HBV-CSU-211- ISO-I       A
HBV-CSU-211- ISO-II      C
HBV-CSU-212              A
HBV-CSU-212- ISO-I       A
HBV-CSU-212- ISO-II      C
HBV-CSU-213              A
HBV-CSU-214              A
HBV-CSU-214- ISO-I       C
HBV-CSU-214- ISO-II      A
HBV-CSU-215              B
HBV-CSU-216              C
HBV-CSU-216-ISO-I        B
HBV-CSU-216-ISO-II       C
HBV-CSU-217              B
HBV-CSU-217-ISO-I        C
HBV-CSU-217-ISO-II       A
HBV-CSU-218              B
HBV-CSU-218-ISO-I        C
HBV-CSU-218-ISO-II       B
HBV-CSU-219              A
HBV-CSU-220              A
HBV-CSU-221              A
HBV-CSU-222              A
HBV-CSU-222- ISO-I       A
HBV-CSU-222- ISO-II      B
HBV-CSU-224              A
HBV-CSU-224-ISO-I        A
HBV-CSU-224-ISO-II       C
HBV-CSU-226              B
HBV-CSU-230              A
HBV-CSU-230- ISO-I       A
HBV-CSU-230- ISO-II      C
HBV-CSU-231              A
HBV-CSU-231-ISO-I        A
HBV-CSU-231-ISO-II       C
HBV-CSU-232              A
HBV-CSU-235              A
HBV-CSU-235-ISO-I        A
HBV-CSU-235-ISO-II       C
HBV-CSU-238              A
HBV-CSU-238- ISO-I       A
HBV-CSU-238- ISO-II      B
HBV-CSU-239              A
HBV-CSU-239- ISO-I       A
HBV-CSU-239- ISO-II      B
HBV-CSU-240- ISO-I       A
HBV-CSU-240- ISO-II      B
HBV-CSU-241              A
HBV-CSU-241- ISO-I       A
HBV-CSU-241- ISO-II      B
HBV-CSU-242              A
HBV-CSU-242-ISO-I        A
HBV-CSU-242-ISO-II       C
HBV-CSU-243              A
HBV-CSU-243-ISO-I        C
HBV-CSU-243-ISO-II       A
HBV-CSU-244              A
HBV-CSU-244- ISO-I       A
HBV-CSU-244- ISO-II      A
HBV-CSU-245              A
HBV-CSU-245- ISO-I       A
HBV-CSU-245- ISO-II      A
HBV-CSU-246              A
HBV-CSU-246- ISO-I       C
HBV-CSU-246- ISO-II      A
HBV-CSU-247              A
HBV-CSU-247-ISO-I        C
HBV-CSU-247-ISO-II       A
HBV-CSU-248              A
HBV-CSU-248- ISO-I       A
HBV-CSU-248- ISO-II      C
HBV-CSU-250              A
HBV-CSU-250- ISO-I       A
HBV-CSU-250- ISO-II      B
HBV-CSU-252              A
HBV-CSU-252-ISO-I        A
HBV-CSU-252-ISO-II       C
HBV-CSU-254              A
HBV-CSU-254-ISO-I        A
HBV-CSU-254-ISO-II       B
HBV-CSU-256              B
HBV-CSU-257              A
HBV-CSU-258              A
HBV-CSU-259              A
HBV-CSU-260              A
HBV-CSU-261              A
HBV-CSU-261- ISO-I       A
HBV-CSU-261- ISO-II      C
HBV-CSU-262              A
HBV-CSU-263              A
HBV-CSU-264              A
HBV-CSU-265              A
HBV-CSU-265- ISO-I       A
HBV-CSU-265- ISO-II      C
HBV-CSU-266              A
HBV-CSU-266-ISO-I        A
HBV-CSU-266-ISO-II       B
HBV-CSU-266-Trans-ISO-I  A
HBV-CSU-266-Trans-ISO-II B
HBV-CSU-267              A
HBV-CSU-267-ISO-I        A
HBV-CSU-267-ISO-II       A
HBV-CSU-268              A
HBV-CSU-268-ISO-I        A
HBV-CSU-268-ISO-II       C
HBV-CSU-269              A
HBV-CSU-269-ISO-I        A
HBV-CSU-269-ISO-II       B
HBV-CSU-270-ISO-I        A
HBV-CSU-270-ISO-II       B
HBV-CSU-271              A
HBV-CSU-271- ISO-I       A
HBV-CSU-271- ISO-II      B
HBV-CSU-272              A
HBV-CSU-272-ISO-I        A
HBV-CSU-272-ISO-II       C
HBV-CSU-273              A
HBV-CSU-276              A
HBV-CSU-276-ISO-I        A
HBV-CSU-276-ISO-II       C
HBV-CSU-276-Trans-ISO-I  A
HBV-CSU-276-Trans-ISO-II B
HBV-CSU-277              A
HBV-CSU-277-ISO-I        A
HBV-CSU-277-ISO-II       C
HBV-CSU-278              A
HBV-CSU-278-ISO-I        A
HBV-CSU-278-ISO-II       C
HBV-CSU-280              A
HBV-CSU-280-ISO-I        B
HBV-CSU-280-ISO-II       A
HBV-CSU-281              A
HBV-CSU-281-ISO-I        A
HBV-CSU-281-ISO-II       B
HBV-CSU-283              A
HBV-CSU-284              A
HBV-CSU-284-ISO-I        A
HBV-CSU-284-ISO-II       B
HBV-CSU-285              A
HBV-CSU-285-ISO-I        A
HBV-CSU-285-ISO-II       A
HBV-CSU-286              A
HBV-CSU-286-ISO-I        A
HBV-CSU-286-ISO-II       B
HBV-CSU-288              A
HBV-CSU-288-ISO-I        A
HBV-CSU-288-ISO-II       B
HBV-CSU-289              A
HBV-CSU-289-ISO-I        A
HBV-CSU-289-ISO-II       B
HBV-CSU-290              A
HBV-CSU-290-ISO-I        A
HBV-CSU-290-ISO-II       B
HBV-CSU-291              A
HBV-CSU-291-ISO-I        A
HBV-CSU-291-ISO-II       C
HBV-CSU-292-ISO-I        A
HBV-CSU-292-ISO-II       B
HBV-CSU-293-ISO-I        A
HBV-CSU-293-ISO-II       C
HBV-CSU-294-ISO-I        A
HBV-CSU-294-ISO-II       B
HBV-CSU-295-ISO-I        A
HBV-CSU-295-ISO-II       B
HBV-CSU-296              B
HBV-CSU-296-ISO-I        A
HBV-CSU-296-ISO-II       B
HBV-CSU-300              A
HBV-CSU-300-ISO-I        A
HBV-CSU-300-ISO-II       C
HBV-CSU-302-ISO-I        A
HBV-CSU-302-ISO-II       C
HBV-CSU-304              A
HBV-CSU-304-ISO-I        A
HBV-CSU-304-ISO-II       C
HBV-CSU-305              A
HBV-CSU-305-ISO-I        A
HBV-CSU-305-ISO-II       B
HBV-CSU-306-ISO-I        A
HBV-CSU-306-ISO-II       C
HBV-CSU-312              A
HBV-CSU-312-ISO-I        A
HBV-CSU-312-ISO-II       B
HBV-CSU-313-ISO-I        A
HBV-CSU-313-ISO-II       B
HBV-CSU-314-ISO-I        A
HBV-CSU-314-ISO-II       B
HBV-CSU-315              A
HBV-CSU-315-ISO-I        A
HBV-CSU-315-ISO-II       A
HBV-CSU-316-ISO-I        A
HBV-CSU-316-ISO-II       A
HBV-CSU-317              A
HBV-CSU-317-ISO-I        A
HBV-CSU-317-ISO-II       A
HBV-CSU-321              A
HBV-CSU-321-ISO-I        A
HBV-CSU-321-ISO-II       C
HBV-CSU-322              A
HBV-CSU-322-ISO-I        A
HBV-CSU-322-ISO-II       C
HBV-CSU-323              A
HBV-CSU-323-ISO-I        A
HBV-CSU-323-ISO-II       B
HBV-CSU-324              A
HBV-CSU-324-ISO-I        A
HBV-CSU-324-ISO-II       B
HBV-CSU-325              A
HBV-CSU-325-ISO-I        A
HBV-CSU-325-ISO-II       C
HBV-CSU-326              A
HBV-CSU-326-ISO-I        A
HBV-CSU-326-ISO-II       C
HBV-CSU-327              A
HBV-CSU-327-ISO-I        A
HBV-CSU-327-ISO-II       B
HBV-CSU-328              A
HBV-CSU-328-ISO-I        A
HBV-CSU-328-ISO-II       C
HBV-CSU-329              A
HBV-CSU-330              A
HBV-CSU-331-ISO-I        A
HBV-CSU-331-ISO-II       B
HBV-CSU-333-ISO-I        A
HBV-CSU-333-ISO-II       B
HBV-CSU-334              A
HBV-CSU-335              A
HBV-CSU-336              A
HBV-CSU-336-ISO-I        A
HBV-CSU-336-ISO-II       B
HBV-CSU-337-ISO-I        A
HBV-CSU-337-ISO-II       B
HBV-CSU-338-ISO-I        A
HBV-CSU-338-ISO-II       B
HBV-CSU-339-ISO-I        A
HBV-CSU-339-ISO-II       B
HBV-CSU-340-ISO-I        A
HBV-CSU-340-ISO-II       B
HBV-CSU-341-ISO-I        A
HBV-CSU-341-ISO-II       B
HBV-CSU-360              A
HBV-CSU-360-ISO-I        B
HBV-CSU-360-ISO-II       A
HBV-CSU-364              A
HBV-CSU-369              A
HBV-CSU-370              A
HBV-CSU-370-ISO-I        A
HBV-CSU-370-ISO-II       B
HBV-CSU-371              A
HBV-CSU-371-ISO-I        A
HBV-CSU-371-ISO-II       B
HBV-CSU-372              A
HBV-CSU-372-ISO-I        A
HBV-CSU-372-ISO-II       B
HBV-CSU-373              A
HBV-CSU-373-ISO-I        A
HBV-CSU-373-ISO-II       A
HBV-CSU-374              A
HBV-CSU-374-ISO-I        A
HBV-CSU-374-ISO-II       A
HBV-CSU-375              A
HBV-CSU-375-ISO-I        A
HBV-CSU-375-ISO-II       B
HBV-CSU-376              A
HBV-CSU-376-ISO-I        A
HBV-CSU-376-ISO-II       B
HBV-CSU-377              A
HBV-CSU-377-ISO-I        A
HBV-CSU-377-ISO-II       B
HBV-CSU-378              A
HBV-CSU-378-ISO-I        A
HBV-CSU-378-ISO-II       B
HBV-CSU-379-ISO-I        A
HBV-CSU-379-ISO-II       A
HBV-CSU-383              A

INCORPORATION BY REFERENCE

All publications and patents mentioned herein, including those items listed below, are hereby incorporated by reference in their entirety for all purposes as if each individual publication or patent was specifically and individually incorporated by reference. In case of conflict, the present application, including any definitions herein, will control.

EQUIVALENTS

While specific embodiments of the subject disclosure have been discussed, the above specification is illustrative and not restrictive. Many variations of the disclosure will become apparent to those skilled in the art upon review of this specification. The full scope of the disclosure should be determined by reference to the claims, along with their full scope of equivalents, and the specification, along with such variations.

Unless otherwise indicated, all numbers expressing quantities of ingredients, reaction conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in this specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present disclosure.

LENGTHY TABLES
The patent application contains a lengthy table section. A copy of the table is available in electronic form from the USPTO web site (). An electronic copy of the table will also be available from the USPTO upon request and payment of the fee set forth in 37 CFR 1.19(b)(3).

Claims

1.-24. (canceled)

25. A compound: or a pharmaceutically acceptable salt thereof.

26. A pharmaceutical composition comprising a compound: or a pharmaceutically acceptable salt thereof, and one or more pharmaceutically acceptable excipient.

27. A method of treating HBV infection in a subject in need thereof, comprising administering to the subject a compound: or a pharmaceutically acceptable salt thereof.