Rho-Kinase Inhibitors
Disclosed are compounds and derivatives thereof, their synthesis, and their use as Rho-kinase inhibitors. These compounds are useful for inhibiting tumor growth, treating erectile dysfunction, and treating other indications mediated by Rho-kinase, e.g., coronary heart disease.
The present invention relates to compounds and derivatives thereof, their synthesis, and their use as Rho-kinase inhibitors. These compounds of the present invention are useful for inhibiting tumor growth, treating erectile dysfunction, and treating other indications mediated by Rho-kinase, e.g., coronary heart disease.
BACKGROUNDThe pathology of a number of human and animal diseases including hypertension, erectile dysfunction, coronary cerebral circulatory impairments, neurodegenerative disorders and cancer can be linked directly to changes in the actin cytoskeleton. These diseases pose a serious unmet medical need. The actin cytoskeleton is composed of a meshwork of actin filaments and actin-binding proteins found in all eukaryotic cells. In smooth muscle cells the assembly and disassembly of the actin cytoskeleton is the primary motor force responsible for smooth muscle contraction and relaxation. In non-muscle cells, dynamic rearrangements of the actin cytoskeleton are responsible for regulating cell morphology, cell motility, actin stress fiber formation, cell adhesion and specialized cellular functions such as neurite retraction, phagocytosis or cytokinesis (Van Aelst, et al. Genes Dev 1997, 11, 2295).
The actin cytoskeleton is controlled by a family of proteins that are a subset of the Ras superfamily of GTPases. This subset currently consists of RhoA through E and RhoG (refereed to collectively as Rho), Rac 1 and 2, Cdc42Hs and G25K and TC10 isoforms (Mackay, et al. J Biol Chem 1998, 273, 20685). These proteins are GTP (guanine nucleotide triphosphate) binding proteins with intrinsic GTPase activity. They act as molecular switches and cycles between inactive GDP (guanine nucleotide diphosphate) bound and active GTP bound states. Using biochemical and genetic manipulations, it has been possible to assign functions to each family member. Upon activation the Rho proteins controls the formation of actin stress fibers, thick bundles of actin filaments, and the clustering of integrins at focal adhesion complexes. When activated the Rac proteins control the formation of lamellopodia or membrane ruffles on the cell surface and Cdc42 controls filopodia formation. Together this family of proteins plays a critical part in the control of key cellular functions including cell movement, axonal guidance, cytokinesis, and changes in cell morphology, shape and polarity.
Depending on the cell type and the activating receptor, the Rho proteins can control different biological responses. In smooth muscle cells, Rho proteins are responsible for the calcium sensitization during smooth muscle contraction. In non-smooth muscle cells the Rho GTPases are responsible for the cellular responses to agonist such as lysophosphatidic acid (LPA), thrombin and thromboxane A2 (Fukata, et al. Trends Pharcol Sci 2001, 22, 32). Agonist response is coupled through heterotrimeric G proteins Galpha12 or Galphal3 (Goetz), et al. Cancer Res 1999, 59, 4732; Buhl, et al. J Biol Chem 1995, 270, 24631) though other receptors may be involved. Upon activation Rho GTPases activate a number of downstream effectors including PIPS-kinase, Rhothekin, Rhophilin, PKN and Rho kinase isoforms ROCK-1/ROKbeta and ROCK-1/ROKalpha (Mackay and Hall J Biol Chem 1998, 273, 20685; Aspenstrom Curr Opin Cell Biol 1999, 11, 95; Amano, et al. Exp Cell Res 2000, 261, 44).
Rho kinase was identified as a RhoA interacting protein isolated from bovine brain (Matsui, et al. Embo J 1996, 15, 2208). It is a member of the myotonic dystrophy family of protein kinase and contains a serine/threonine kinase domain at the amino terminus, a coiled-coil domain in the central region and a Rho interaction domain at the carboxy terminus (Amano, et al. Exp Cell Res 2000, 261, 44). Its kinase activity is enhanced upon binding to GTP-bound RhoA and when introduced into cells, it can reproduce many of the activities of activated RhoA. In smooth muscle cells Rho kinase mediates calcium sensitization and smooth muscle contraction and inhibition of Rho kinase blocks 5-HT and phenylephrine agonist induced muscle contraction. When introduced into non-smooth muscle cells, Rho kinase induces stress fiber formation and is required for the cellular transformation mediated by RhoA (Sahni, et al. Curr Biol 1999, 9, 136). Rho kinase regulates a number of downstream proteins through phosphorylation, including myosin light chain (Somlyo, et al. J Physiol (Land) 2000, 522 Pt 2, 177), the myosin light chain phosphatase binding subunit (Fukata, et al. J Cell Biol 1998, 141, 409) and LIM-kinase 2 (Sunni, et al. J Bio Chem 2001, 276, 670).
Inhibition of Rho kinase activity in animal models has demonstrated a number of benefits of Rho kinase inhibitors for the treatment of human diseases. Several patents have appeared claiming (+)-trans-4-(1-aminoethyl)-1-(pyridin-4-ylaminocarbonyl)cyclohexane dihydrochloride monohydrate (WO-00078351, WO-00057913) and substituted isoquinolinesulfonyl (EP-00187371) compounds as Rho kinase inhibitors with activity in animal models. These include models of cardiovascular diseases such as hypertension (Uehata, et al. Nature 1997, 389, 990), atherosclerosis (Retzer, et al. FEES Lett 2000, 466, 70), restenosis (Eto, et al. Am J Physiol Heart Circ Physiol 2000, 278, H1744; Negoro, et al. Biochem Biophys Res Commun 1999, 262, 211), cerebral ischemia (Uehata, et al. Nature 1997, 389, 990; Seasholtz, et al. Circ Res 1999, 84, 1186; Hitomi, et al. Life Sci 2000, 67, 1929; Yamamoto, et al. J Cardiovasc Pharmacol 2000, 35, 203), cerebral vasospasm (Sato, et al. Circ Res 2000, 87, 195; Kim, et al. Neurosurgery 2000, 46, 440), penile erectile dysfunction (Chitaley, et al. Nat Med 2001, 7, 119), central nervous system disorders such as neuronal degeneration and spinal cord injury (Hara, et al. J Neurosurg 2000, 93, 94; Toshima, et al. Stroke 2000, 31, 2245) and in neoplasias where inhibition of Rho kinase has been shown to inhibit tumor cell growth and metastasis (Itoh, et al. Nat Med 1999, 5, 221; Somlyo, et al. Biochem Biophys Res Commun 2000, 269, 652), angiogenesis (Uchida, et al. Biochem Biophys Res Commun 2000, 269, 633; Gingras, et al. Biochem J2000, 348 Pt 2, 273), arterial thrombotic disorders such as platelet aggregation (Klages, et al. J Cell Biol 1999, 144, 745; Retzer, et al. Cell Signal 2000, 12, 645) and leukocyte aggregation (Kawaguchi, et al. Eur J Pharmacol 2000, 403, 203; Sanchez-Madrid, et al. Embo J 1999, 18, 501), asthma (Setoguchi, et al. Br J Pharmacol 2001, 132, 111; Nakahara, et al. Eur J Pharmacol 2000, 389, 103), regulation of intraoccular pressure (Honjo, et al. Invest Ophthalmol Vis Sci 2001, 42, 137) and bone resorption (Chellaiah, et al. J Biol Chem 2000, 275, 11993; Zhang, et al. J Cell Sci 1995, 108, 2285).
The inhibition of Rho kinase activity in patients has benefits for controlling cerebral vasospasms and ischemia following subarachnoid hemorrhage (Pharma Japan 1995, 1470, 16).
SUMMARY OF THE INVENTIONThe compounds and their derivatives presented in this invention are useful as Rho Kinase inhibitors and thus have utilities in the treatment of cardiovascular disease, e.g., hypertension, atherosclerosis, restenosis, cerebral ischemia, and cerebral vasospasm, as well as neuronal degeneration, spinal cord injury, cancers of the breast, colon, prostate, ovaries, brain and lung and their metastases, thrombotic disorders, asthma, glaucoma and osteoporosis.
In addition, the compounds of the invention are useful to treat erectile dysfunction, i.e., erectile dysfunction mediated by Rho-kinase. Erectile dysfunction can be defined as an inability to obtain or sustain an erection adequate for intercourse, WO 94/28902, U.S. Pat. No. 6,103,765 and U.S. Pat. No. 6,124,461.
The invention involves compounds of formula I
- wherein R1 and R2 are each independently H, halo, alkyl, optionally substituted by halo up to the perhalo level, cycloalkyl, alkenyl, alkynyl, NO2, NH2, NR6R7, or furyl, thienyl, pyridyl, trifluoromethyl or phenyl each optionally substituted with NH2, NO2, trifluoromethyl or alkoxy,
- R1 and R2 may be taken together to form a ring of from 5 to 7 members optionally interrupted by N and optionally substituted on N by benzyl;
- R3 is NH2 or —NH— phenyl optionally substituted with halo, C1-C4 alkyl, trifluoromethyl, nitro or amino;
- R4 is
or indol-5-yl (optionally) substituted on the N with pyridyl;
- X is a linker substituted at the 3 or 4 position of the ring and is selected from O, S, —S—CH2—, —(CH2)m—, or —(C═O)—;
- A is phenyl optionally substituted with alkylthio or OH,
- pyridyl,
- quinolyl or
- isoquinolyl;
each R5 independently is halo, alkyl optionally substituted by halo up to the perhalo level, cycloalkyl, alkoxy, alkenyl, alkynyl, NO2, NH2, or trifluoromethyl;
n is 0, 1, 2, 3 or 4;
m is 1 or 2; and
R6 and R7 are each independently H, alkyl, cycloalkyl, or phenyl optionally substituted with halo, CF3, alkyl, nitro or amino; or
R6 and R7 may form, together with the N atom to which they are attached, a heterocyclic ring optionally substituted with alkyl, optionally interrupted by 0, or optionally fused to phenyl;
with the proviso that formula I does not include the following compounds:
Preferred compounds of formula I include those wherein
- R1 and R2 are each independently H, halo, C1-12 alkyl optionally substituted by halo up to the perhalo level, C2-12, alkenyl, C2-12-alkynyl, NO2, NH2, NR6R7, alkyl, furyl, thienyl, pyridyl, phenyl optionally substituted with NO2, trifluoromethyl or NR6R7;
- R1 and R2 may be taken together to form a ring of from 5 to 7 members optionally interrupted by N and (optionally) substituted on N by benzyl;
- R3 is NH2 or —NH— phenyl optionally substituted with halo, C1-C4 alkyl, trifluoromethyl, nitro or amino;
- R4 is
or indol-5-yl (optionally) substituted on the N with pyridyl;
- X is a linker substituted at the 3 or 4 position of the ring and is selected from O, S, —S—(CH2)m—, or —(C═O)—;
- A is phenyl optionally substituted by C1-4 alkylthio or OH,
- pyridyl,
- quinolyl or
- isoquinolyl;
each R5 independently is halo, C1-C12 alkyl, optionally substituted by halo, up to the perhalo level, C2-12-alkenyl, C2-12-alkynyl, NO2, NH2 or trifluoromethyl;
n is 0, 1, 2, 3 or 4;
m is 1 or 2; and
R6 and R7 are each independently H, C1-C6 alkyl, or phenyl optionally substituted with halo, CF3, C1-C4 alkyl, nitro or amino, with the exception of the compounds previously cited.
-
- Particularly preferred compounds include those wherein
- (i) X is not S or A is not pyridyl, or both;
- (ii) X is not S or —S—CH2—;
- (iii) n is 1-4
- (iv) n is 1-4 and each R5 is independently is halo, C3-C12 alkyl optionally substituted by halo up to the perhalo level, C2-C12-alkenyl, C2-12-alkynyl, NO2, NH2 or trifluoromethyl; or
- (v) the compound of formula I is not
The terms identified above have the following meaning throughout:
“Alkyl” means straight or branched chain alkyl groups having from one to about twelve carbon atoms. Such groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, neo-pentyl, 2-pentyl, n-hexyl, 2-hexyl, 3-hexyl, dodecyl, 2,3-dimethylbutyl and the like.
“Cycloalkyl” means saturated monocyclic alkyl groups of from 3 to about 8 carbon atoms and includes such groups as cyclopropyl, cyclopentyl, cyclohexyl and the like.
“Alkenyl” means straight or branched chain alkenyl groups having from two to about twelve carbon atoms. Such groups include vinyl, allyl, isopropenyl, 3-butenyl and the like.
“Alkynyl” means straight or branched chain alkynyl groups having from two to about twelve carbon atoms. Such groups include ethynyl, propargyl, 3-pentynyl, 3-heptynyl, 1-methyl-2-butynyl and the like.
“Alkoxy” means straight or branched chain alkoxy groups having from about one to eight carbon atoms and includes such groups as methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy and the like.
“Halo” means fluoro, chloro, bromo, or iodo. Preferred are fluoro, chloro and bromo, more preferably fluoro and chloro.
When an alkyl substituent is described as being substituted by oxo, it means substitution by a doubly bonded oxygen atom, which forms together with the carbon to which it is attached, a carbonyl group —(C═O)—.
The term “optionally substituted” means that the moiety so modified may be unsubstituted or substituted with the identified substituent(s).
When any moiety is described as being substituted, it can have one or more of the indicated substituents that can be located at any available position on the moiety. When there are two or more substituents on any moiety, each substituent is defined independently of any other substituent and can, accordingly, be the same or different.
The compounds of the Formula I can be made according to routine, conventional chemical methods, and/or as disclosed below, from starting materials which are either commercially available or producible according to routine, conventional chemical methods. General methods for the preparation of the compounds are given below, and the preparation of representative compounds is specifically illustrated in the Examples.
General Methods of Preparation
Compounds of Formula I may be prepared using one of the general methods summarized below in Reaction Schemes 1-3, from either commercially available or readily prepared starting materials. Preparation of starting material is described in Reaction Schemes 4-6.
In the first methods, illustrated in Reaction Scheme 1, the reaction of a chloropyrimidine of Formula II with a substituted aromatic compound of Formula where R1-R4 are as defined above, may be accomplished under either basic or acidic conditions (Reaction Scheme 1).
Alternatively, when R1 is an aryl group, a two-step scheme may be employed. In the first step, the Formula III compound is allowed to react with the dichloropyrimidine of Formula IIa under acidic conditions as in Reaction Scheme 1. In the second step, the R1 group is introduced by palladium-catalyzed coupling of a boronic acid of Formula R1B(OH)2 (e.g., Suzuki coupling) to provide compounds of Formula I in which R1 is aryl (Reaction Scheme 2).
The compounds of Formula I, where R1 is NR6R7, may be prepared conveniently by reaction the chloropyrimidine of Formula Ia with a variety of amines of Formula R6R7NH, usually in a higher boiling polar solvent such as n-butanol, and at an elevated temperature, e.g., 90-120° C. as shown in Reaction Scheme 3.
Intermediate chloropyrimidines of Formula II and aryl amines of Formula III are either commercially available or may be prepared by methods well known in the art. For example, a pyrimidone can be converted to the corresponding chloropyrimidine H by reaction with POCl3, and reduction of nitro aromatic compounds under standard conditions (e.g., Fe, HOAc) provides aryl amines of Formula III. Further illustrative methods are depicted in Reaction Schemes 4-6 below. For example, in Reaction Scheme 4, Formula III compounds in which R4 is
A is 2 or 4 pyridyl, and X is O or S, are prepared by a nucleophilic aromatic substitution reaction of a haloarene (A-halo) with a phenol or thiophenol of Formula IV, carried out in a polar solvent such as DMF and assisted by a base such as potassium carbonate (Reaction Scheme 4).
Intermediates of Formula Mb may be prepared as shown in Reaction Scheme 5 in two steps from a nitroaromatic compound of Formula V, where Z represents either CH or N. The nitro aromatic compound is allowed to react in basic media at elevated temperatures, and the resulting nitro aromatic compound is reduced by standard means, e.g., iron and acetic acid.
A wide variety of chloropyrimidines of Formula II where R3 is NH2 and R1 is other than NR6R7, may be prepared by the route shown in Reaction Scheme 6 below. Reaction of a carboxylic acid of Formula VI, where R1 is other than NR6R7, with a substituted Meldrum's acid of Formula VII (prepared, for example by alkylation of Meldrum's acid with R2-halo and base), gives a ketoester of Formula VIII. The pyrimidone compound of Formula IX is formed by reaction of compound VIII with guanidine in the presence of an acid in protic solvent such as ethanol. The pyrimidone of Formula IX is then converted to the chloropyrimidine IIb, (II, where R3 is NH2) under typical conditions, e.g., POCl3 and heat.
Without further elaboration, it is believed that one skilled in the art can, using the preceding descriptions, utilize the present invention to its fullest extent. The following preferred specific embodiments are, therefore, to be construed as merely illustrative, and not limitative of the remainder of the disclosure in any way whatsoever.
In the foregoing and in the following examples, an temperatures are set forth uncorrected in degrees Celsius; and, unless otherwise indicated, all parts and percentages are by weight.
The entire disclosure of all applications, patents and publications, cited above or below, and U.S. Provisional Application Ser. No. 60/349,987, filed Jan. 23, 2002, are hereby incorporated by reference.
Abbreviations and Acronyms
- When the following abbreviations are used herein, they have the following meaning:
- Ac2O acetic anhydride
- anhy anhydrous
- n-BuOH n-butanol
- t-BuOH t-butanol
- CD3OD methanol-d4
- Celite® diatomaceous earth filter agent,® Celite Corp.
- CH2Cl2 methylene chloride
- CI-MS chemical ionization mass spectroscopy
- conc concentrated
- dec decomposition
- DME dimethoxyethane
- DMF N,N-dimethylformamide
- DMSO dimethylsulfoxide
- ELSD evaporative light scattering detector
- EtOAc ethyl acetate
- EtOH ethanol (100%)
- Et2O diethyl ether
- Et3N triethylamine
- HPLC ES-MS high performance liquid chromatography-electrospray mass spectrometry
- LC liquid chromatography
- MPLC medium pressure liquid chromatography
- MS mass spectrometry
- NMM 4-methylmorpholine
- Ph3P triphenylphosphine
- Pd(dppf)Cl2 [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium(II)
- Pd(PPh3)4 tetrakis(triphenylphosphine)palladium(0)
- Pd(OAc)2 palladium acetate
- P(O)Cl3 phosphorous oxychloride
- RT retention time (HPLC0)
- rt room temperature
- THF tetrahydrofuran
- TFA trifluoroacetic acid
- TLC thin layer chromatography
All reactions were performed in flame-dried or oven-dried glassware under a positive pressure of dry argon, and were stirred magnetically unless otherwise indicated. Sensitive liquids and solutions were transferred via syringe or cannula, and introduced into reaction vessels through rubber septa. Commercial grade reagents and solvents were used without further purification. Thin layer chromatography (TLC) was performed on Analtech UNIPLATE™ pre-coated glass-backed silica gel 60 A F-254 250 μm plates. Column chromatography (flash chromatography) was performed on a Biotage system using 32-63 micron, 60 A, silica gel pre-packed cartridges. Proton ('H) nuclear magnetic resonance (NMR) spectra were measured with a Varian (300 MHz) spectrometer with residual protonated solvent (CHCl3 δ 7.26; MeOH δ 3.30; DMSO ε 2.49) as standard. Low-resolution mass spectra (MS) were either obtained as electron impact (EI) mass spectra or as fast atom bombardment (FAB) mass spectra.
The IUPAC name was obtained using the ACD/ILab Web service.
A. Preparation of Chloropyrimidine Intermediates Intermediate A1 Preparation of 2-amino-4-chloro-5,6-dimethyl-pyrimidineTo a solution of ethyl 2-acetoacetate (6.0 g, 41.6 mmol) and guanidine carbonate (5.6 g, 31.2 mmol) in EtOH (32 mL) was added 12 N HCl (350 μL). The mixture was refluxed for 16 h. After the reaction was cooled to room temperature, the solid was collected by filtration and washed with EtOH. A solution of the solid in 1 N NaOH was refluxed for 3 h. After the reaction was cooled to room temperature, the aqueous mixture was adjusted to pH=5 with concentrated acetic acid. The resulting precipitate was collected by filtration, washed with water and then with hexanes, and dried under vacuum. Desired compound (6.34 g, 45.6 mmol; 100% yield); 1H NMR (D2O; NaOD) δ 1.47 (s, 3H), 1.29-1.30 (m, 2H), 1.22 (s, 3H); ES MS [M+H]+=140.
Step 2. Preparation of 2-amino-4-chloro-5,6-dimethyl-pyrimidineThe product of the previous step (2.0 g, 14.4 mmol) and phosphorus oxychloride (6 mL, 57.5 mmol), was refluxed for 4 h. The reaction was cooled to rt and poured over ice. The mixture was separated and the aqueous layer was extracted with chloroform (3×75 mL). The aqueous mixture was adjusted to pH=9 with concentrated ammonium hydroxide. The resulting solid product was collected by filtration, washed with water, and dried under vacuum. Desired compound (963 mg, 6.1 mmol; 43% yield); mp=212-220° C.; ES MS [M+H]+=158; TLC (CH2Cl2-MeOH, 90:10); Rf=0.72.
Intermediate A2 Preparation of 2-amino-4-chloro-6-(4-pyridyl)pyrimidineA solution of guanidine carbonate (7.1 g, 39 mmol, 1.5 eq), ethyl isonicotinoyl acetate (10 g, 51.76 mmol), and hydrochloric acid (0.75 mL, 9.0 mmol) in absolute ethanol (80 mL) was refluxed under argon overnight. The precipitate formed was filtered, washed with ethanol and dried. The solid was then dissolved in 1 N NaOH (100 mL) and refluxed for 2 h. The reaction mixture was then cooled to room temperature, acidified with glacial acetic acid, and the solid formed was filtered and dried to afford the desired product as a white solid (5.45 g, 56%). 1H-NMR (DMSO-d6) δ 6.24 (s, 1H), 6.79 (bs, 2H), 7.85 (d, J=5.1 Hz, 2H), 8.62 (d, J=5.3 Hz, 2H), 11.22 (bs, 1H).
Step 2. Preparation of 2-amino-4-chloro-6-(4-pyridyl)pyrimidineA solution of 2-amino-4-hydroxy-6-(4-pyridyl)pyrimidine (5.45 g, 29 mmol) in POCl3 (12 mL) was refluxed under argon for 5 h, The reaction mixture was cooled to room temperature, poured over ice, and allowed to stir at room temperature for 2 h to ensure the quenching of POCl3. At this time, the mixture was made basic upon addition of 1 N NaOH and the brown solid was filtered to afford 4.52 g of crude product, which was used without further purification (NMR analysis showed 1:1 product/starting material). The filtrate formed more solid upon standing at room temperature (1 g, NMR analysis showed 2:1 product/starting material). 1H-NMR (DMSO-d6) δ 7.34 (bs, 2H), 7.38 (s, 1H), 7.99 (d, J=4.2 Hz, 2H), 8.72 (d, J=4.6 Hz, 2H).
Intermediate A3 Preparation of 2-amino-4-chloro-6-(2-thienyl)pyrimidineA solution of thiophene-2-carboxylic acid (8.9 g, 68.5 mmol), 2,2-dimethyl-1,3-dioxane-4,6-dione (12.0 g, 81.6 mmol), and 4-dimethylaminopyridine (17.0 g, 138 mmol) in dry CH2Cl2 (100 mL) was cooled to 0° C. and treated with a solution of 1,3-dicyclohexylcarbodiimide (75 mL, 1.0 M in CH2Cl2, 75 mmol). The reaction was allowed to stir at room temperature for 2 h and the dicyclohexylurea was then filtered and washed with CH2Cl2. The filtrate was concentrated at reduced pressure and the residue was dissolved in absolute ethanol (400 mL). The solution was then treated with a solution of p-toluenesulfonic acid monohydrate (32 g, 168 mmol) in absolute ethanol (100 mL) and refluxed under argon for 1 h. At this time, the ethanol was removed at reduced pressure and the residue was dissolved in EtOAc and washed sequentially with H2O (300 mL), saturated NaHCO3 (200 mL), 1 N HCl (200 mL), saturated NaCl, and dried (MgSO4). The solvent was removed at reduced pressure and the residue was filtered through a pad of silica with 10% EtOAc/90% hexanes to afford the desired product as an oil (13 g, 96%). TLC (20% EtOAc/80% hexane) Rf 0.21; 1H-NMR (DMSO-d6) δ 1.17 (t, J=7.01, 3H), 4.06-4.14 (m, 4H), 7.25 (t, J=5.1 Hz, 1H), 7.98 (d, J=3.8 Hz, 1H), 8.06 (d, J=4.9 Hz, 1H).
Step 2. Preparation of 2-amino-4-hydroxy-6-(2-thienyl)pyrimidineThe procedure was similar to that used for Intermediate A2, step 1, using ethyl-2-(thienyl-2-oyl)acetate as starting material. (43% yield). TLC (6% MK/H/94% CH2Cl2) Rf 0.23; MS ES 194 [M+H]+; 1H-NMR (DMSO-d6) δ 6.06 (s, 1H), 6.70 (bs, 2H), 7.11 (t, J=4.9 Hz, 1H), 7.64 (d, J=4.9 Hz, 1H), 7.70 (d, J=3.6 Hz, 1H), 10.95 (bs, 1H).
Step 3. Preparation of 2-amino-4-chloro-6-(2-thienyl)pyrimidineThe procedure was similar to that of Intermediate A2, step 2, using 2-amino-4-hydroxy-6-(2-thiophene)pyrimidine as starting material. It afforded 33% yield after purification on silica with 15% EtOAc/85% hexanes. TLC (20% EtOAc/80% hexanes) Rf 0.29; 1H-NMR (DMSO-d6) δ 7.16-7.23 (m, 4H), 7.77 (dd, J=0.8, 5.0 Hz, 1H), 7.98 (dd, J=1.0, 3.8 Hz, 1H).
Intermediate A4 Preparation of 2-amino-4-chloro-6(2-furyl)pyrimidineThe general procedure for the preparation of Intermediate A2, (step 1) was used; (37% yield). MS (ES) 178 [M+H]+.
Step 2. Preparation of 2-amino-4-chloro-6-(2-furyl)pyrimidineA solution of 2-amino-4-hydroxy-6-(2-furyl)pyrimidine (1.40 g, 7.9 mmol) in POCl3 (4 mL) was refluxed under argon for 2 h. The POCl3 was distilled; the residue was diluted with EtOAc and poured over iced saturated NaHCO3. The layers were separated and the aqueous was extracted with EtOAc (100 mL). The combined extracts was washed with saturated NaCl, dried (MgSO4), and the solvent removed at reduced pressure to afford 0.5 g of crude product, which was used without further purification. TLC (20% EtOAc/80% hexane) Rf 0.26; 1H-NMR (DMSO-d6) δ 6.68 (dd, J=1.7, 3.4 Hz, 1H), 6.94 (s, 1H), 7.25 (dd, J=1, 3.7 Hz, 1H), 7.91 (dd, J=0.8, 1.9 Hz, 1H).
Intermediate A5 Preparation of 6-benzyl-4-chloro-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-2-amineTo EtOH (16 mL) cooled to 0° C. (ice/H2O bath) was added Na spheres (204 mg, 8.9 mmol). The mixture was stirred until all Na dissolved. Methyl 1-benzyl-4-oxo-3-piperidine-carboxylate hydrochloride (3.0 g, 10.1 mmol) and guanidine carbonate (1.4 g, 7.6 mmol) were added. The mixture was refluxed for 16 h. After the reaction was cooled to room temperature, the solid was collected by filtration, washed with EtOH, and dried under vacuum. Desired compound (2.58 g, 10.0 mmol; 99+% yield); mp=202-212° (dec.); ES MS [M+H]+=257; TLC (CH2Cl2-MeOH, 90:10); Rf=0.20.
Step 2. Preparation of 6-benzyl-4-chloro-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-2-amineA solution of the product from step 1 (3.5 g, 13.7 mmol) in POCl3 (52 mL) was refluxed under argon for 5 h. The reaction mixture was cooled to room temperature, poured over ice, and allowed to stir at room temperature for 2 h to ensure the quenching of POCl3. At this time, the mixture was made basic upon addition of ammonium hydroxide and was extracted with CH2Cl2 (3×200 mL). The combined organics were washed with 1N NaOH followed by brine, dried (MgSO4), and concentrated under reduced pressure. The residue was taken up in benzene and was made acidic upon the addition of 1N HCl in diethyl ether. The brown solid was filtered to afford 0.35 g of crude product, which was used without further purification. ES MS [M+H]+=275.
Intermediate A6 Preparation of 2-amino-6-(trifluoromethyl)-4-pyrimidinyl 4-methylbenzenesulfonateTo a solution of 2-amino-6-(trifluoromethyl)-4(3H)-pyrimidinone (250 mg, 1.4 mmol), triethylamine (196 μL, 1.4 mmol), N,N-dimethylaminopyridine (17 mg, 0.14 mmol), in CH2Cl2 (13 mL) cooled to 0° C. was added p-toluenesulfonyl chloride (534 mg, 2.8 mmol). The mixture was stirred at room temperature for 16 h. The mixture was diluted with CH2Cl2, washed with H2O (2×20 mL) followed by brine, dried (Na2SO4), evaporated, and dried under vacuum. Desired compound (466 mg, 1.4 mmol; 99+% yield; ES MS [M+H]+=140.
Using the above methods for the preparation of A1-A6 and substituting the appropriate starting materials, the following pyrimidine intermediates were also prepared.
To a solution of 5-nitroindole (7.0 g, 43.2 mmol) and 4-chloropyridine hydrochloride (7.8 g, 51.8 mmol) in DMF (43 mL) was added potassium tert-butoxide (12.1 g, 108.0 mmol), portionwise. The reaction was heated at 100° C. for 48 h. The mixture was allowed to cool to room temperature and poured into water (400 mL). The resulting solid was removed by filtration and dried under vacuum. Desired compound (6.04 g, 25.3 mmol; 58% yield); 1H NMR (DMSO-d6) δ 8.76 (dd, J=1.7, 4.5, 2H), 8.68 (d, J=2.2, 1H), 8.06-8.13 (m, 2H), 7.92 (d, J=9.2, 1H), 7.75 (dd, J=1.5, 4.6, 2H), 7.07 (dd, J=0.9, 3.5, 1H); ES MS [M+H]+=240.
Step 2. Preparation of 1-(4-pyridinyl)-1H-indol-5-amineA mixture of the product from step 1 (8.27 g, 34.6 mmol) and 10% palladium-on-charcoal catalyst (827 mg) in ethyl acetate (166 mL) and EtOH (9 mL) was stirred under hydrogen at atmospheric pressure for 48 h. Further catalyst (414 mg) was added and the reaction was stirred for 24 h. Again, further catalyst (414 mg) was added and the reaction was stirred an additional 24 h. The catalyst was removed by filtration through diatomaceous earth and the solvent removed from the filtrate by evaporation. The residue was triturated with ether, collected by filtration, and dried under vacuum. Desired compound (4.67 g, 22.3 mmol; 65% yield); mp=149-154° C.; ES MS [M+H]+=210; TLC(CH2Cl2-MeOH, 95:5); Rf=0.29.
Intermediate B2 Preparation of 4-[(4-aminophenyl)sulfanyl]phenolTo a solution of nitrobenzenesulfonyl chloride (4 g, 21 mmol) in ether (25 mL) was added phenol (1.97 g, 20 mmol) as a solution in ether (25 mL). After being stirred for 15 h at rt, the mixture was concentrated to afford a crude solid which was recrystallized from acetic acid. Desired compound (4.0 g, 16.2 mmol, 76% yield). TLC (Hexanes/EtOAc, 70:30); Rf=0.54.
Step 2. Preparation of 4-[(4-aminophenyl)sulfanyl]phenolTo a solution of the product of step 1 (4 g, 16.2 mmol) in EtOH (500 mL) was added SnCl2.2H2O (18.3 g, 81 mmol) The solution was warmed to reflux. After being stirred for 3 h, the mixture was allowed to cool to rt, and the volatiles were removed by rotary evaporation. The resultant slurry was suspended in EtOAc, and solid NaHCO3 was added. Subsequently, the mixture was filtered, and the filtered solid was washed thoroughly with EtOAc. The organic filtrate was washed with water, and the aqueous washes were extracted with EtOAc. The combined organic extracts were washed with brine, dried (MgSO4), filtered, and concentrated to afford an orange solid, which was used without additional purification. Desired compound (3.0 g, 13.8 mmol, 86% yield). TLC (Hexanes/EtOAc, 70:30); RF 0.34.
Intermediate B3 Preparation of (3-aminophenyl)[4-(methylsulfanyl)phenyl]methanone3-nitrobenzoylchloride (5.0 g, 26.94 mmol) was added to a solution of thioanisole (3.16 mL, 26.94 mmol) and 1,2-dichlorethane (95 mL). The resulting reaction mixture was cooled to 0° C. (ice/H2O bath) and 0.5 equivalents of aluminum trichloride (1.8 g, 13.47 mmol) was added. The reaction was allowed to stir for 15 min at this temperature and the cold bath was removed followed by addition of the remaining equivalents of AlCl3 (2.51 g, 18.87). The reaction solution turned a dark greenish/yellow and was allowed to stir at room temp. for 18 h, after which time the reaction was quenched slowly with H2O (50 mL). The mixture was diluted with CH2Cl2 (50 mL) and washed with H2O (3×50 mL), and the combined organic phases were washed with satd NaHCO3 (50 mL), dried (MgSO4) and concentrated under reduced pressure. The crude material was purified by silica gel column chromatography (EtOAc/hexane, 1/4) to afford 3.3 g (44%) of 4-(methylsulfanyl)phenyl](3-nitrophenyl)methanone as a solid. EI-LRMS m/z 274 (M+); TLC Rf 0.68 (EtOAc/Hex, 2/3).
Step 2 Preparation of (3-aminophenyl)[4-(methylsulfanyl)phenyl]methanonePrepared analogously to Intermediate B2, step 2. The crude product was purified by flash column chromatography, eluting with 70:30 Hexanes/EtOAc. TLC: (Hexanes/EtOAc, 70:30); Rf=0.15.
Intermediate B4 Preparation of 4-(4-aminophenoxy)phenolA mixture of p-nitrofluorobenzene (25 g, 0.177 mol), dihydroquinone (19.5 g, 0.177 mol), and sodium hydroxide (7.08 g, 0.177 mol) in EtOH/H2O (1:1 v/v, 176 mL) was heated at reflux for 20 h, and subsequently allowed to cool to room temperature. The mixture was filtered, the filtrate was made acidic with dilute aqueous HCl, and the resultant precipitate filtered to afford the crude product as a yellow solid. The desired product was recrystallized from EtOH. (15 g, 0.064 mol, 37% yield). TLC (Hexanes/EtOAc, 70:30); Rf=0.44.
Step 2. Preparation of 4-(4-aminophenoxy)phenolTo a solution of the product of step 1 in EtOH (100 mL) was added 10% palladium on carbon (200 mg). After being stirred under an atmosphere of hydrogen overnight, the mixture was filtered through Celite®. The volatiles were removed from the filtrate to provide the crude product which was purified by flash column chromatography eluting with Hexanes/EtOAc (85:15, followed by 75:25). Desired product (1.5 g, 7.45 mmol, 86%). TLC (Hexanes/EtOAc, 70:30); Rf=0.41.
Intermediate B5 Preparation of 4-(4-pyridinylthio)anilineTo a solution of 4-aminothiophenol (20.2 g, 156.5 mmol) in anhydrous DMF (200 mL) was added 4-chloropyridine hydrochloride (24.4 g, 161.0 mmol) followed by potassium carbonate (44 g, 318.4 mmol). The reaction mixture was heated at 80° C. overnight, then diluted with ethyl acetate (400 mL) and water (400 mL). The aqueous layer was back-extracted with ethyl acetate (2×200 mL). The combined organic layers were washed with a saturated aqueous NaCl solution (200 mL), dried over anhy MgSO4, and concentrated under reduced pressure. The residue was filtered through a pad of silica with ethyl acetate and the resulting material was triturated with an ethyl ether/hexane solution to afford the desired product (24.7 g, 78%). TLC (50% ethyl acetate/50% hexane) Rf 0.25; 1H-NMR (DMSO-d6) δ 5.67 (bs, 2H), 6.65 (d, J=8.4 Hz, 2H), 6.88 (d, J=6.2 Hz, 2H), 7.19 (d, J=8.4 Hz, 2H), 8.27 (d, J=6.2 Hz, 2H), MS[M+H]+=203.
Intermediate B6 Preparation of 4-[(E)-2-pyridinyl)ethyl]anilineTo an oven dried 500 mL 3-necked flask was added (4-nitrobenzyl)triphenylphosphonium bromide (15 g, 30.42 mmol) followed by the addition of THF (100 mL). The solution was cooled to 0° C. in an ice bath. Potassium t-butoxide (3.9 g, 33.02 mmol) was then added in one portion resulting in an orange suspension. The suspension was maintained at 0° C. while a solution of 4-pyridine-2-carboxaldehyde (2.7 g, 24.70 mmol) in THF (20 mL) was added in 10 minutes. The ice bath was removed and the reaction was stirred at room temperature for 2 h. At this time, the reaction was quenched with saturated ammonium chloride solution (50 mL) and stirred for 15 minutes. The mixture was then extracted with ethyl acetate (2×100 mL), the combined extracts was washed with saturated aqueous NaCl solution (100 mL) and dried (MgSO4). The solvent was removed at reduced pressure and the residue was chromatographed on silica with 0-50% ethyl acetate in hexanes to afford the desired product (1.8 g, 32%). TLC (50% ethyl acetate/50% hexane) Rf 0.28; 1H-NMR (DMSO-d6) δ 6.84 (d, J=12.4 Hz, 1H), 6.96 (d, J=12.4 Hz, 1H), 7.14 (d, J=6.2 Hz, 2H), 7.45 (d, J=8.7 Hz, 2H), 8.15 (d, J=8.7 Hz, 2H), 8.47 (d, J=6.2 Hz, 2H).
Step 2. Preparation of 4-[2-(4-pyridinyl)ethyl]anilineTo a dry 50 mL flask flushed with argon was added 10% Pd on carbon (285 mg) followed by the addition of ethanol (12 mL) and the product from step 1 (1.8 g, 8.0 mmol). At this time, the argon line was replaced with a hydrogen balloon and the reaction was stirred overnight. The mixture was filtered through a pad of Celite® and the filtrate was concentrated at reduced pressure. The solid residue was triturated with ethyl ether/hexanes to afford the desired product (1.2 g, 67%). TLC (4% acetone/96% methylene chloride) Rf 0.09; 1H-NMR (DMSO-d6) δ 2.67-2.83 (m, 4H), 4.83 (bs, 2H), 6.45 (d, J=8.2 Hz, 2H), 6.84 (d, J=8.2 Hz, 2H), 7.20 (d, J=6 Hz, 2H), 8.41 (d, J=6 Hz, 2H).
Intermediate B7 Preparation of 3-fluoro-4-(4-pyridinylsulfanyl)anilineA solution of 4-mercaptopyridine (4.2 g, 35.6 mmol), 3,4-difluoronitrobenzene (5.7 g, 35.7 mmol), and potassium carbonate (12.4 g, 89.7 mmol) in anhydrous DMF (40 mL) was stirred at 40° C. and under argon for 3 h. TLC showed complete reaction. The mixture was diluted with ethyl acetate (100 mL) and water (100 mL) and the aqueous layer was back-extracted with ethylacetate (2×100 mL). The organic layers were washed with a saturated NaCl solution (100 mL), dried (MgSO4), and concentrated under reduced pressure. The crude product was purified by column chromatography with 50% ethyl acetate/50% hexanes. It afforded the desired product as a yellow solid (6.3 g, 71%). TLC (50% EtOAc/50% hexane) Rf 0.53; 1H-NMR (DMSO-d6) δ 7.27 (dd, J=0.76, 4.2 Hz, 2H), 7.78 (dt, J=0.76, 7.2 Hz, 1H), 8.11-8.15 (m, 1H), 8.28-8.33 (m, 1H), 8.5 (dd, J=1.4, 4.6 Hz, 2H), MS [M+H]+=251.
Step 2. Preparation of 3-fluoro-4-(4-pyridinylsulfanyl)anilineA slurry of 3-fluoro-4-pyridinylthio)nitrobenzene (6.3 g, 25.2 mmol), iron powder (6.0 g, 107.4 mmol), acetic acid (100 mL), and water (1 mL) were stirred at room temperature overnight. The mixture was diluted with Et2O (100 mL) and water (100 mL). The aqueous phase was adjusted to pH 5 with a 4 N NaOH solution. The combined organic layers were washed with an aqueous saturated NaCl solution (100 mL), dried (MgSO4), and concentrated under reduced pressure. The residue was purified by column chromatography with 50% ethyl acetate/50% hexanes. It afforded the desired product as a white solid (4.8 g, 86%). TLC (50% EtOAc/50% hexane) Rf 0.28; 1H-NMR (DMSO-d6) δ 6.04 (bs, 2H), 6.47-6.51 (m, 2H), 6.91 (d, J=6.1 Hz, 2H), 7.22 (t, J=8.4 Hz, 1H), 8.30 (d, J=6.4 Hz, 2H).
Using similar methods to those described for the preparation of Intermediates B1-B7, the following additional compounds were also prepared:
The compound can be obtained by oxidizing 3-chloro-4,5-difluoroaniline, described in JP 05059067, with hydrogen peroxide in trifluoroacetic acid according to a process described in Heaton, A. et al., J. Fluorine Chem. 1997, 81 (2), 133-138 and Krapcho, A. P. et al., J. Org. Chem. 1990, 55 (21), 5662-5664 for the preparation of analogous derivatives.
Intermediate C2 4-[(2-Fluoro-4-nitrophenyl) sulphanyl]pyridine21 g (188.9 mmol) of 4-mercaptopyridine, 30.05 g (188.9 mmol) of 3,4-difluoro-nitrobenzene and 60.05 g (434.5 mmol) of potassium carbonate are dissolved in dimethylformamide, and the mixture is stirred at 40° C. for 3 hours. The reaction solution is then diluted with 500 mL of ethyl acetate and 300 mL of water. The aqueous phase is extracted five times with in each case 100 mL of ethyl acetate. The combined organic phases are washed with 200 mL of saturated sodium chloride solution, dried over sodium sulphate and concentrated under reduced pressure using a rotary evaporator. The residue is purified by MPLC (mobile phase: ethyl acetate:cyclohexane 1:1).
This gives 37.3 g (79% of theory) of product.
1H-NMR (300 MHz, DMSO-d6): δ=7.28 (dd, 2H), 7.79 (t, 1H), 8.15 (dd, 1H), 8.30 (dd, 1H), 8.50 (dd, 2H)
LC-MS (method 4): RT=2.68 min
MS (ESIpos): m/z=251 (M+H)+
Intermediate C3 below can be prepared from the appropriate mercapto or hydroxy heterocycles and their corresponding 4-fluoro- and 4-chloronitrobenzene derivatives, analogously to the procedure described for C2.
37 g (147.9 mmol) of C2 are dissolved in 1000 mL of ethanol, and 143.86 mL (2.95 mol) of hydrazine hydrate and 4 g of palladium on carbon are added. The reaction mixture is stirred under reflux overnight. After cooling, the mixture is filtered off with suction through silica gel, and the filter cake is washed with ethanol. The filtrate is concentrated under reduced pressure using a rotary evaporator. The residue is suspended in diethyl ether and filtered off with suction. The precipitate is then suspended in water and filtered off with suction. The product is washed two more times with a little water. Drying under high vacuum gives 27.3 g (84% of theory) of product.
1H-NMR (300 MHz, DMSO-d6): δ=6.02 (br.s, 2H), 6.49-6.54 (m, 2H), 6.93 (dd, 2H), 7.23 (t, 1H), 8.32 (dd, 2H)
LC-MS (method 4): RT 0.96 min
MS (ESIpos): m/z=221 (M+H)+
Intermediate C5 can be prepared analogously to the procedure described for C4 from the appropriate starting materials.
3.19 g (11.205 mmol) of C3 are dissolved in 200 mL of ethanol. 638 mg (2.81 mmol) of platinum(IV) oxide are then added, and the mixture is stirred at RT and atmospheric pressure under an atmosphere of hydrogen for 2 hours. For work-up, the reaction solution is filtered off with suction through kieselguhr and washed thoroughly with ethanol. The filtrate is concentrated under reduced pressure.
This gives 2.755 g (81% of theory) of product.
1H-NMR (200 MHz, DMSO-d6): δ=6.37 (s, 2H), 6.49 (dd, 1H), 6.72-6.74 (m, 1H), 6.93 (dd, 2H), 8.34 (dd, 2H)
HPLC (method 1): RT=168 min
MS (ESIpos): m/z=255 (M+H)+
Intermediate C7 3,5-difluoro-4-(4-pyridinylsulfanyl)anilineis synthesized analogously to C6 from 4-[(2,6-difluoro-4-nitrophenyl)sulfanyl]pyridine by catalytic reduction with hydrogen on Platin(IV)oxide.
1H-NMR (300 MHz, DMSO-d6): δ=6.38 (br. s, 2H), 6.40 (m, 2H), 6.98 (dd, 2H), 8.35 (dd, 2H)
HPLC (method 1): RT=3.56 min
4-[(2,6-difluoro-4-nitrophenyl)sulfanyl]pyridineis synthesized analogously to C2 from 4-mercaptopyridine and 1,2,3-trifluoro-5-nitrobenzene.
1H-NMR (200 MHz, DMSO-d6): δ=7.22 (dd, 2H), 8.32 (mc, 2H), 8.44 (dd, 2H) HPLC (method 1): RT=3.64 min 1,2,3-trifluoro-5-nitrobenzene
is synthesized analogously to Cl from 3,4,5-trifluoraniline by oxidation with hydrogenperoxide in trifluoroacetic acid.
GC-MS (method 13): RT=3.15 min
MS (ESIpos): m/z=177 (M+)
Intermediate C8 3-chloro-4-(4-pyridinylsulfanyl)anilineis synthesized analogously to C6 from 4-[(2-chloro-4-nitrophenyl)sulfanyl]pyridine by catalytic reduction with hydrogen on Platin(IV)oxide.
LC-MS (method 7): RT=2.70 min
MS (ESIpos): m/z=237 (M+H)+
4-[(2-chloro-4-nitrophenyl)sulfanyl]pyridineis synthesized analogously to C2 from 4-mercaptopyridine and 1,2-dichloro-4-nitrobenzene.
1H-NMR (200 MHz, DMSO-d6): δ=7.42 (dd (2H), 7.55 (d, 1H), 8.19 (dd (1H), 8.47 (d, 1H), 8.50 (dd, 2H)
HPLC (method 1): RT=3.72 min
HPLC, LCMS and GCMS Methods: Method 1 HPLCInstrument: HP 1100 with DAD detection; column: Kromasil RP-18, 60 mm×2 mm, 3.5 μm; mobile phase: A=5 mL of HClO4/1 of H2O, B=acetonitrile; gradient: 0 min 2% B, 0.5 min 2% B, 4.5 min 90% B, 6.5 min 90% B; flow rate: 0.75 mL/min; temp.: 30° C.; detection UV 210 nm.
Method 7 (LCMS):Instrument: Micromass Platform LCZ, HP1100; column: Symmetry C18, 50 mm×2.1 mm, 3.5 μm; mobile phase A: water+0.05% formic acid, mobile phase B: acetonitrile+0.05% formic acid; gradient: 0.0 min 90% A→4.0 min 10% A→6.0 min 10% A; oven: 40° C.; flow rate: 0.5 mL/min; UV detection: 208-400 nm.
Method 10 (LCMS):Instrument: Waters Alliance 2790 LC; column: Symmetry C18, 50 mm×2.1, 3.5 μm; mobile phase A: water+0.1% formic acid, mobile phase B: acetonitrile+0.1% formic acid; gradient: 0.0 min 5% B→5.0 min 10% B→6.0 min 10% B; temperature: 50° C.; flow rate: 1.0 mL/min; UV detection: 210 nm.
Method 12 (LCMS):Instrument: Micromass Platform LCZ, HP 1100; column: Grom-SIL1200DS-4 HE, 50 mm×2.0 mm, 3 μm; mobile phase A: 11 water+1 mL 50% formic acid, mobile phase B: 11 acetonitrile+1 mL 50% formic acid; gradient: 0.0 min 100% A 0.2 min 100% A→2.9 min 30% A→3.1 min 10% A→4.5 min 10% A; temperature: 55° C.; flow rate: 0.8 mL/min; UV detection: 208-400 nm
Method 13 (GCMS):Instrument: Micromass GCT, GC6890; column: Restek RTX-35MS, 30 m×250 μm×0.25 μm; carrier gas: helium; flow rate: 0.88 mL/min; initial temperature: 60° C.; front injector temp.: 250° C.; gradient: 60° C. (1 min const.), 16° C./min up to 300° C. then 1 min const. 300° C.
The following additional compounds may be produced analogously to the relevant examples above with the (+) and (−) enantiomers being separated on a chiral column:
anti isomer, racemic mixture
anti isomer, enantiomer 1
anti isomer, enantiomer 2
anti isomer, racemic
(+) and (−) enantiomers of the above compound may be separated on a chiral column.
2-Amino-4-chloro-6-ethylpyrimidine (A8, 50 mg, 0.23 mmol) and Intermediate B2 (40 mg, 0.25 mmol) were suspended in a mixture of 0.01 M aqueous HCl (230 μL) and 1-butanol (230 μL). The mixture was refluxed overnight. The reaction was cooled to room temperature and quenched with NaHCO3 (satd eq). The precipitated solid was filtered and subsequently purified by reversed phase chromatography on a YMC Pack-pro C18 column (trademark) eluting with acetonitrile/H2O (10:90-90:10 gradient). Desired compound (40.5 mg, 0.11 mmol, 51% yield); mp=181-184° C., TLC (95:5 CH2Cl2/MeOH); Rf=0.13
Examples 2-14
-
- Using the above procedures, the following examples of pyridines were synthesized and are summarized in Table 3.
By selecting combinations of the appropriate Intermediates A1-A21 with Intermediates B1-B17, a variety of products were prepared in like manner and are described in Examples 15-18
Example 15 Preparation of N-(2-amino-6-methyl-4-pyrimidinyl)-N-[4-(3-pyridinylsulfanyl)phenyl]aminePrepared in 5% yield from A7 and B19: TLC (7% MeOH in CH2Cl2) Rf 0.49; MS (ES) 310 [M+H]+; 1H-NMR. (DMSO-d6) δ 2.13 (s, 3H), 5.94 (s, 1H), 6.48 (bs, 2H), 7.31-7.39 (m, 3H), 7.56 (td, 8.2 Hz, 1H), 7.81 (d, J=8.9 Hz, 2H), 8.38-8.40 (m, 2H), 9.50 (bs, 1H).
Example 16 Preparation of N-(2-amino-6-methyl-4-pyrimidinyl)-N-[3-(4-pyridinylsulfanyl)phenyl]aminePrepared in 29% yield from A7 and B20:TLC (6% MeOH in CH2Cl2) Rf 0.37; MS (ES) 310 [M+H]+; 1H-NMR (DMSO-d6) δ 2.08 (s, 3H), 5.86 (s, 1H), 6.17 (bs, 2H), 7.06 (d, J=6.0 Hz, 2H), 7.09 (d, J=7.5 Hz, 1H), 7.39 (t, J=7.8 Hz, 1H), 7.78 (t, J=2.2 Hz, 1H), 7.99 (dd, J=1.4, 8.1 Hz, 1H), 8.36 (d, J=6.3 Hz, 2H), 9.18 (bs, 1H).
Example 17 Preparation of N-(2-anilino-6-methyl-4-pyrimidinyl)-N-[4-(4-pyridinylsulfanyl)phenyl]aminePrepared in 1% yield from A16 and 135: TLC (50% EtOAc/50% hexanes) Rf 0.15; MS (ES) 386 [M+H]+; 1H-NMR (DMSO-d6) δ 2.25 (s, 3H), 6.14 (s, 1H), 6.89 (t, J=7.4 Hz, 1H), 6.97 (d, J=5.7 Hz, 2H), 7.23 (t, J=7.2 Hz, 2H), 7.47 (d, J=9.0 Hz, 2H), 7.71 (dd, J=0.9, 8.6 Hz, 2H), 7.89 (d, J=8.5 Hz, 2H), 8.33 (bs, 2H), 9.21 (s, 1H), 9.55 (s, 1H).
Example 18 Preparation of N-(2-amino-6-methyl-4-pyrimidinyl)-N-[4-(5-quinolinyloxy)phenyl]aminePrepared in 71% yield from A7 and B21: TLC (6% MeOH in CH2Cl2) Rf 0.34; MS (ES) 344 [M+H]+; 1H-NMR (DMSO-d6) δ 2.08 (s, 3H), 5.85 (s, 1H), 6.11 (bs, 2H), 6.88 (d, J=7.3 Hz, 1H), 7.04 (d, J=8.6 Hz, 2H), 7.56 (dd, J=4.0, 8.5 Hz, 1H), 7.65 (t, J=8.5 Hz, 1H), 7.73-7.76 (m, 3H), 8.57 (d, J=8.6 Hz, 1H), 8.94 (d, J=3.9 Hz, 1H), 9.03 (bs, 1H).
Examples 19-22Using the following general method, Examples 19-22 were prepared
A suspension of Intermediate A (1.0 mmol), Intermediate B (1.0 mmol), and HCl (0.1 mL) in H2O (1.0 mL) was heated to 70° C. in a 5 mL reaction vial overnight. The reaction mixture was diluted with MeOH, treated with saturated NaHCO3, coated on silica and purified by MPLC (Biotage) with 5% MeOH in CH2Cl2.
Example 19 Preparation of N-(2-amino-6-phenyl-4-pyrimidinyl)-N-[3,5-dichloro-4-(4-pyridinylsulfanyl)phenyl]aminePrepared in 40% yield from A17 and B14: TLC (4% MeOH in CH2Cl2) Rf 0.42; MS (ES) 440 [M+H]+; 1H-NMR (DMSO-d6) δ 6.53 (s, 1H), 6.67 (bs, 2H), 6.94 (d, J=6.1 Hz, 2H), 7.47-7.51 (m, 3H), 7.93-7.96 (m, 2H), 8.18 (s, 2H), 8.36 (d, J=5.7 Hz, 2H), 9.88 (bs, 1H).
Example 20 Preparation of N[2-amino-6-(3-nitrophenyl)-4-pyrimidinyl]-N[3-fluoro-4-(4-pyridinylsulfanyl)phenyl]aminePrepared in 97% yield from A20 and B7: TLC (50% EtOAc/50% hexanes) Rf 0.15; MS (ES) 435 [M+H]+; 1H-NMR (DMSO-d6) δ 6.69 (s, 1H), 6.78 (bs, 2H), 6.98 (d, J=4.8 Hz, 2H), 7.46-7.57 (m, 2H), 7.79 (t, J=7.9 Hz, 1H), 8.33-8.35 (m, 5H), 8.79 (s, 1H), 9.94 (bs, 1H).
Example 21 Preparation of N-[2-amino-6-(2-furyl)-4-pyrimidinyl]-N-[3-fluoro-4-(4-pyridinylsulfanyl)phenyl]aminePrepared in 12% yield from A4 and B7: TLC (6% MeOH in CH2Cl2) Rf 0.37; MS (ES) 380 [M+H]+; 1H-NMR (DMSO-d6) δ 6.45 (s, 1H), 6.58 (bs, 2H), 6.64 (dd, J=1.9, 3.5 Hz, 1H), 6.97-6.70 (m, 3H), 7.44 (dd, J=1.9, 8.4 Hz, 1H), 7.53 (t, J=8.6 Hz, 1H), 7.84 (d, J=1.6 Hz, 1H), 8.29-8.35 (m, 3H), 9.80 (bs, 1H).
Example 22 Preparation of N-[2-amino-6-(2-thienyl)-4-pyrimidinyl]-N-[3-fluoro-4-(4-pyridinylsulfanyl)phenyl]aminePrepared in 29% yield from A3 and B7. TLC (4% MeOH in CH2Cl2) Rf 0.22; MS (ES) 396 [M+H]%'H-NMR (DMSO-d6) δ 6.47 (s, 1H), 6.61 (bs, 2H), 6.98 (d, J=6.4 Hz, 2H), 7.15-7.18 (m, 1H), 7.43-7.68 (m, 4H), 8.29-8.36 (m, 3H), 9.79 (bs, 1H).
Using analogous methods, Example 23 is synthesized from 4-chloro-6-furan-3-yl-2-methyl-pyrimidine and Intermediate B7.
Example 23 Preparation of 6-furan-3-yl-N4-[4-(pyridin-4-yl-sulfanyl)-phenyl]-pyrimidine-2,4-diamineThe following general procedure and the appropriate Intermediates A and B provided the compounds described in Table 4 below.
A mixture of Intermediate B (0.250 mmol) and Intermediate (0.25 mmol) in 0.01 M aqueous HCl (500 μL) was refluxed for 6 h. The reaction was cooled to room temperature and the solvent was evaporated by vacuum. The residue was purified by reverse phase chromatography on a YMC Pack-pro® C18 column eluting with acetonitrile/H2O (10:90-90:10 gradient) to give the desired compound.
In some cases, the compound was further purified by preparative TLC eluting with CH2Cl2-MeOH (90:10) to give the desired product.
2-Amino-4,6 dichloroprimidine (A21, 12 mmol) and 3-fluoro-4-(4-pyridinylthio)-aniline (B7.12 mmol) were suspended in water (150 mL) and treated with 10 drops of concentrated hydrochloric acid. The mixture was stirred at 100° C. overnight. The clear solution was then neutralized with ammonium hydroxide. The precipitated yellow product was filtered, washed with water, and purified by column chromatography with 1-3% MeOH in CH2Cl2 to give the desired product as a white solid (1.98 g, 47%).
Step 2. Preparation of N[2-amino-6-(4-ethoxyphenyl)-4-pyrimidinyl]-N-[3-fluoro-4-(4-pyridinylsulfanyl)phenyl]amineA solution of N-(2-amino-6-chloro-4-pyrimidinyl)-N-[3-fluoro-4-(4-pyridinylsulfanyl)phenyl]amine from step 1 in toluene (2 mL) in ethanol (1 mL) was treated with aqueous sodium carbonate solution (2M, 0.5 mL). The mixture was then treated with 4-ethoxyphenylboronic acid (0.36 mmol), tetrakis(triphenylphosphine)-palladium (0.009 mmol), and allowed to stir at 120° C. under argon overnight. At this time, the solvents were removed at reduced pressure and the residue was purified by preparative silica gel with 3% MeOH in CH2Cl2 to afford the desired product as a white solid (21 mg).
Parallel Synthesis Methods Example 28-33An equivalent of N-(2-amino-6-chloro-4-pyrimidinyl)-N[3-fluoro-4-(4-pyridinylsulfanyl)phenyl]amine (Example 26, step 1, 0.1 mmol) and four equivalents of the desired amine (R6R7NH) were suspended in n-butanol (1 mL) and shaken at 110° C. overnight to 2 days. The solvent was removed at reduced pressure and the residue was purified either by preparative silica gel plate or by HPLC. The products were checked by LC-MS and TLC and are listed in Table 5 below.
A dry flask under argon was charged with 10% palladium on carbon (20 mg). A solution of N[2-amino-6-(3-nitrophenyl)-4-pyrimidinyl]-N-[3-fluoro-4-(4-pyridinylsulfanyl)phenyl]amine (Example 20, 200 mg, 0.46 mmol) in ethanol (12 mL) and EtOAc (1 mL) was added via syringe through a septa to the palladium on carbon. The flask was then fitted with a hydrogen balloon and stirred at room temperature for 48 h. At this time the palladium was filtered through a pad of Celite®. The filtrate was coated on silica and purified on the MPLC (Biotage) with 2-8% MeOH in CH2Cl2 to afford the desired product as a solid (120 mg, 64%). TLC (6% MeOH in CH2Cl2) Rf 0.26; MS (ES) 405 [M+H]+; 1H-NMR (DMSO-d6) δ 5.22 (bs, 2H), 6.45 (s, 1H), 6.49 (bs, 2H), 6.62-6.65 (m, 1H), 6.98 (d, J=6.4 Hz, 2H), 7.02-7.16 (m, 3H), 7.43-7.55 (m, 2H), 8.30-8.35 (m, 3H), 9.75 (bs, 1H).
Examples 35 to 41 listed in the table below can be prepared analogously to the procedure described in Example 1 using the following starting materials:
ROCK-1 activity criteria: 0 no effect (<40% inhibition), 1 effect (>40% inhibition). The assay tests for inhibition of ROCK-1 phosphorylation of MBP (Myelin Basic Protein). The reaction (100 μl final volume) is carried out in polypropylene 96-well plates in 50 mM HEPES buffer pH 7.5 containing 5 mM MgCl2 and 1 mM DTT. For each well, gstROCK1 (0.25 μgs of BAYER DRT gstROCK1) is combined with MBP (1 μg) in reaction buffer (70 μl combined volume). Inhibitors (5 μL of 20× conc. in 40% DMSO) are added to each well to give an 8 point dose response range from 1.0 μM to 0.5 nM. The reaction is begun by adding 25 μl of ATP (4×=12 μM) in reaction buffer containing 0.8 μCi of gamma-ATP (4×) for a final concentration of 3 μM cold and 0.2 μCi hot ATP. Plates were incubated for 1 hour at room temperature with the reaction being stopped by addition of 7 μL of 1 N HCl. The radioactively labeled MBP was transferred to P30 filtermats (EG&G Wallac), washed in 1% phosphoric acid followed by brief washes in water. The filtermats were then dried and the incorporation of 33P detected by liquid scintillation counting. Background 33P incorporation is determined by ROCK1 autophosphorylation without MBP. The data are expressed as percent inhibition: % inhibition=1−((cpm with inhibitor-background)/(cpm without inhibitor−background))*100.
Claims
1. A compound of formula I or indol-5-yl (optionally) substituted on N with pyridyl;
- wherein R1 and R2 are each independently H, halo, alkyl optionally substituted by halo up to perhalo, cycloalkyl, alkenyl, alkynyl, NO2, NH2, NR6R3, or furyl, thienyl, pyridyl, trifluoromethyl or phenyl each optionally substituted with NH2, NO2, trifluoromethyl or alkoxy; or
- R1 and R2 may be taken together to form a ring of from 5 to 7 members optionally interrupted by N and optionally substituted on N by benzyl;
- R3 is NH2 or —NH— phenyl optionally substituted with halo, C1-C4 alkyl, trifluoromethyl, nitro or amino;
- R4 is
- X is a linker substituted at the 3 or 4 position of the ring and is O, S, —S—CH2—, —(CH2)m—, or —(C═O)—;
- A is phenyl optionally substituted with alkylthio or OH, pyridyl, quinolyl or isoquinolyl;
- each R5 independently is halo, alkyl optionally substituted by halo up to perhalo, cycloalkyl, alkoxy, alkenyl, alkynyl, NO2, NH2, or trifluoromethyl;
- n is 0, 1, 2, 3 or 4;
- m is 1 or 2; and
- R6 and R7 are each independently H, alkyl, cycloalkyl, or phenyl optionally substituted with halo, CF3, alkyl, nitro or amino; or
- R6 and R7 may form, together with the N atom to which they are attached, a heterocyclic ring optionally substituted with alkyl, optionally interrupted by 0, or optionally fused to phenyl; or a pharmaceutically acceptable salt thereof,
- with the proviso that formula I does not include the following compounds:
2. A compound of formula I according to claim 1, wherein or indol-5-yl (optionally) substituted on the N with pyridyl;
- R1 and R2 are each independently H, halo, C1-12-alkyl optionally substituted by halo up to perhalo, C2-12, alkenyl, C2-12-alkynyl, NO2, NH2, NR6R7, alkyl, furyl, thienyl, pyridyl, phenyl optionally substituted with NO2, trifluoromethyl or NR6R7; or
- R1 and R2 together form a ring of from 5 to 7 members optionally interrupted by N and optionally substituted on N by benzyl;
- R3 is NH2 or —NH— phenyl optionally substituted with halo, C1-C4 alkyl, trifluoromethyl, nitro or amino;
- R4 is
- X is a linker substituted at the 3 or 4 position of the ring and is selected from O, S, —S—CH2)m—, or —(C═O)—;
- A is phenyl optionally substituted by C1-4 alkylthio or OH, pyridyl, quinolyl or isoquinolyl;
- each R5 independently is halo, C1-C12 alkyl, optionally substituted by halo, up to the perhalo level, C2-12-alkenyl, C2-12-alkynyl, NO2, NH2 or trifluoromethyl;
- n is 0, 1, 2, 3 or 4;
- m is 1 or 2; and R6 and R7 are each independently H, C1-C6 alkyl, or phenyl optionally substituted with halo, CF3, C1-C4 alkyl, nitro or amino.
3. A compound according to claim 1, wherein X is not S or A is not pyridyl.
4. A compound according to claim 1, wherein X is not S or —S—CH2.
5. A compound according to claim 1, wherein n is 1-4.
6. A compound according to claim 1, wherein n is 1-4 and each R5 is independently halo, C3-C12 alkyl optionally substituted by halo up to the perhalo level, C2-12-alkenyl, C2-12-alkynyl, NO2, NH2 or trifluoromethyl.
7. A compound according to claim 1, which is 6-tert-butyl-N4-(1-pyridin-4-yl-1H-indol-5-yl)-pyrimidine-2,4-diamine, N4-(1-pyridin-4-yl-1H-indol-5-yl)-6,7,8,9-tetrahydro-5H-cycloheptapyrimidine-2,4-diamine, 7-benzyl-N4-(1-pyridin-4-yl-1H-indol-5-yl)-5,6,7,8-tetrahydro-pyrido[3,4-d]pyrimidine-2,4-diamine, N4-[4-(pyridin-4-ylsulfanyl)-phenyl]-6,7,8,9-tetrahydro-5H-cycloheptapyrimidine-2,4-diamine, N4-[3-fluoro-4-(pyridin-4-ylsulfanyl)-phenyl]-6-trifluoromethyl-pyrimidine-2,4-diamine, N4-[3-fluoro-4-(pyridin-4-ylsulfanyl)-phenyl]-6,7-dihydro-5H-cyclopentapyrimidine-2,4-diamine, 4-[4-(2-amino-pyrimidin-4-ylamino)-phenylsulfanyl]-phenol, 4-[4-(2-amino-6-ethyl-pyrimidin-4-ylamino)-phenylsulfanyl]-phenol, 4-[4-(2-amino-6-isopropyl-pyrimidin-4-ylamino)-phenylsulfanyl]-phenol, 4-[4-(2-amino-6-tert-butyl-pyrimidin-4-ylamino)-phenylsulfanyl]-phenol, 4-[4-(2-amino-5-chloro-6-methyl-pyrimidin-4-ylamino)-phenylsulfanyl]-phenol, [3-(2-amino-5-chloro-6-methyl-primidin-4-ylamino)-phenyl]-(4-methylsulfanyl-phenyl)-methanone, 4-[4-(2-amino-5-chloro-6-methyl-pyrimidin-4-ylamino)-phenoxy]-phenol, N4-[4-(pyridin-4-ylsulfanyl)-phenyl]-6,7,8,9-tetrahydro-5H-cycloheptapyrimidine-2,4-diamine, N4-[3-fluoro-4-(pyridin-4-ylsulfanyl)-phenyl]-6-trifluoromethyl-pyrimidine-2,4-diamine, N4-[3-fluoro-4-(pyridin-4-ylsulfanyl)-phenyl]-6,7-dihydro-5H-cyclopentapyrimidine-2,4-diamine, 6-(2,6-dimethyl-morpholin-4-yl)-N4-[3-fluoro-4-(pyridin-4-ylsulfanyl)-phenyl]-pyrimidine-2,4-diamine, dihydro-indol-1-yl)-N4-[3-fluoro-4-(pyridin-4-ylsulfanyl)-phenyl]pyrimidine-2,4-diamine, N′-[3-fluoro-4-(pyridin-4-ylsulfanyl)-phenyl]-N″,N″-dipropyl-pyrimidine-2,4,6-triamine, N4-[3-fluoro-4-(pyridin-4-ylsulfanyl)-phenyl]-6-morpholin-4-yl-pyrimidine-2,4-diamine, N′-[3-fluoro-4-(pyridin-4-ylsulfanyl)-phenyl]-N′-isopropyl-pyrimidine-2,4,6-triamine, N′-cyclopentyl-N″-[3-fluoro-4-(pyridin-4-ylsulfanyl)-phenyl]-pyrimidine-2,4,6-triamine, 4-({4-[(2-amino-6-ethyl-4-pyrimidinyl)amino]phenyl}sulfanyl)phenol, N-(2-amino-6-methyl-4-pyrimidinyl)-N-[4-(3-pyridinylsulfanyl)phenyl]amine, N-(2-amino-6-methyl-4-pyrimidinyl)-N-[3-(4-pyridinylsulfanyl)phenyl]amine, N-(2-anilino-6-methyl-4-pyrimidinyl)-N-[4-(4-pyridinylsulfanyl)phenyl]amine, N-(2-amino-6-methyl-4-pyrimidinyl)-N-[4-(5-quinolinyloxy)phenyl]amine, N-(2-amino-6-phenyl-4-pyrimidinyl)-N-[3,5-dichloro-4-(4-pyridinylsulfanyl)phenyl]amine, N-[2-amino-6-(3-nitrophenyl)-4-pyrimidinyl]-N[3-fluoro-4-(4-pyridinylsulfanyl)phenyl]amine, N-[2-amino-6-(2-furyl)-4-pyrimidinyl]-N-[3-fluoro-4-(4-pyridinylsulfanyl)phenyl]amine, N-[2-amino-6-(2-thienyl)-4-pyrimidinyl]-N-[3-fluoro-4-(4-pyridinylsulfanyl)phenyl]amine, or N-[2-amino-6-(4-ethoxyphenyl)-4-pyrimidinyl]-N-[3-fluoro-4-(4-pyridinylsulfanyl)phenyl]amine.
8. A compound according to claim 1, of the formula
9. A compound according to claim 1, of the formula
10. A compound according to claim 1, of the formula
11. A method of treating an indication mediated by Rho-kinase, comprising administering a compound of claim 1.
12. A method of treating hypertension, atherosclerosis, restenosis, cerebral ischemia, cerebral vasospasm, neuronal degeneration, spinal cord injury, cancer of the breast, colon, prostate, ovaries, brain or lung, thrombotic disorders, asthma, glaucoma, osteoporosis or erectile dysfunction, comprising administering to host in need thereof a compound according to claim 1.
13. A process according to claim 11, wherein the host is a human.
14. A process according to claim 12, wherein the host is a human.
15. A process for the preparation of a compound of claim 1, comprising reacting and optionally, where R1 is NR6R7, reacting the chloropyrimidine of Formula Ia with an amine of Formula R6R7NH.
Type: Application
Filed: Nov 4, 2011
Publication Date: Mar 1, 2012
Inventors: Dhanapalan Nagarathnam (Bethany, CT), Jacques Dumas (Bethany, CT), Holia Hatoum-Mokdad (Hamden, CT), Stephen Boyer (Fairfield, CT), Chunguang Wang (Hamden, CT), Hans Pluempe (Wuppertal), Achim Feurer (Wilhelmsfeld), Samir Bennabi (Wuppertal)
Application Number: 13/289,782
International Classification: A61K 31/5377 (20060101); C07D 401/14 (20060101); C07D 471/04 (20060101); C07D 401/12 (20060101); C07D 405/14 (20060101); C07D 409/14 (20060101); C07D 413/14 (20060101); A61K 31/505 (20060101); A61K 31/506 (20060101); A61K 31/517 (20060101); A61K 31/519 (20060101); A61P 9/12 (20060101); A61P 9/10 (20060101); A61P 25/00 (20060101); A61P 25/28 (20060101); A61P 35/00 (20060101); A61P 7/02 (20060101); A61P 11/06 (20060101); A61P 27/06 (20060101); A61P 19/10 (20060101); A61P 15/00 (20060101); C07D 239/48 (20060101);