Abstract: Provided is a supercritical fluid chromatography method, system, and components comprising such a system wherein a non-polar solvent may replace a portion or all of a polar solvent for the purpose of separating or extracting desired sample molecules from a combined sample/solvent stream. The method and system are designed to eliminate or reduce the amount of polar solvent necessary for chromatographic separation and/or extraction of desired samples to less than or equal to twenty percent polar solvent within the total volume concentration of the total solvents used, and the technique may include one or more of a supercritical fluid chiller, a supercritical fluid pressure-equalizing vessel, and a supercritical fluid cyclonic separator. The supercritical fluid chiller and the use of the chiller allow efficient and consistent pumping of liquid-phase gases employing off-the-shelf HPLC pumps in the supercritical chromatography system using liquid-phase gas mobile phase.

Abstract: Disclosed are an S-(carboxymethyl)-cysteine pharmaceutical compound (I), and a preparation method and use thereof. Also disclosed are an S-(carboxymethyl)-D-cysteine ammonium salt monohydrate, and use thereof in preparation of medicines for preventing and treating respiratory system diseases such as chronic obstructive pulmonary diseases, in particular in preparation of expectorants. The compounds can reduce airway resistance and production of oxides in rat COPD models, increase the level of antioxidants, and alleviate damage caused by the oxides and inflammatory mediators to lungs.

Abstract: The present invention relates to 2-(substituted sulphur, sulphone or sulphoxide)-3-(substituted phenyl)propionic acid derivatives, 2-(substituted oxygen)-3-(substituted phenyl)propionic acid derivatives, benzoic acid derivatives, and derivatives of 2-methyl-2-(phenoxy or phenylthio)propanoic acid and 2-(methyl or ethyl)-2-(phenoxy or phenylthio)butanoic acid, to processes for preparing such compounds, to their use in the treatment of inflammatory conditions, and to pharmaceutical compositions containing them.

Abstract: Method for enantioseparation of a chiral system with compound formation comprising a pair of enantiomers. The method comprises the steps of: placing the chiral system to be processed, which is optically enriched by a target enantiomer, in the 3-phase region of the ternary phase diagram of chiral compound forming systems to achieve the establishment of the solid/liquid phase equilibria; phase-separating the liquid and solid phase formed by the placing step; shifting the eutectic composition of the remaining liquid towards a lower eutectic composition (xE) until the overall composition is located in the 2-phase region of the ternary phase diagram of chiral compound forming systems; and performing crystallization in the 2-phase region of the ternary phase diagram for obtaining the target enantiomer in the solid phase. In some cases the shifting step can be skipped.

Abstract: The present invention provides a L-enantiomers selective composite membrane useful for separation of optical isomers and the process for the preparation thereof. The invention further provides a membrane based pressure driven separation process for separation of enantiomers from their mixture to obtain optical pure isomers. The present invention also provides a membrane based method for optical resolution of racemic mixtures of amino acids to obtain optically pure amino acids.

Abstract: Enantiomerically pure L-tert-leucine and D-tert-leucine were prepared from (DL)-tert-leucine by diastereomeric salt formation using dibenzoyl-d-tartaric acid as the resolving agent.

Abstract: The invention concerns a method for separating a racemic compound-forming chiral substance by a cyclic crystallization process which is conducted in at least one first crystallization unit (10) and in at least one second crystallization unit (18), wherein in a first process cycle an enantiomer is crystallized in the first crystallization unit (10) and a racemic compound is crystallized in the second crystallization unit (18), wherein in a second process cycle the enantiomer is crystallized in the second crystallization unit (18) and the racemic compound is crystallized in the first crystallization unit (10), wherein during each process cycle in at least one process sub-step (B?C, F?G) a mother liquor (12) being contained in the first crystallization unit (10) is mutually exchanged with a mother liquor (20) being contained in the second crystallization unit (18). An auto-seeding process sub-step is applied at the beginning of a process cycle.

Abstract: Subject of the invention is a method for the production of L-carnitine, comprising the steps of (a) providing a solution comprising at least 5% (w/w) carnitine in a first solvent, wherein the carnitine is a mixture of D- and L-carnitine, (b) optionally seeding the solution with L-carnitine crystals, (c) adding an second solvent, in which the L-carnitine is not soluble or has a low solubility, (d) isolating crystals comprising L-carnitine.

Abstract: The invention concerns a method for separating a racemic compound-forming chiral substance by a cyclic crystallization process which is conducted in at least one first crystallization unit (10) and in at least one second crystallization unit (18), wherein in a first process cycle an enantiomer is crystallized in the first crystallization unit (10) and a racemic compound is crystallized in the second crystallization unit (18), wherein in a second process cycle the enantiomer is crystallized in the second crystallization unit (18) and the racemic compound is crystallized in the first crystallization unit (10), wherein during each process cycle in at least one process sub-step (B?C, F?G) a mother liquor (12) being contained in the first crystallization unit (10) is mutually exchanged with a mother liquor (20) being contained in the second crystallization unit (18). An auto-seeding process sub-step is applied at the beginning of a process cycle.

Abstract: Methods for producing compounds having activity as an ?2? ligand are provided.

Abstract: A process for the resolution of two enantiomers which involves inducing the preferential crystallization of one enantiomer by adjusting the composition of a suspension or solution including a racemic mixture of the two enantiomers and a solvent, by evaporation of the latter.

Abstract: Enantiomerically pure L-tert-leucine and D-tert-leucine were prepared from (DL)-tert-leucine by diastereomeric salt formation using dibenzoyl-d-tartaric acid as the resolving agent.

Abstract: The invention concerns a method for separating a racemic compound-forming chiral substance by a cyclic crystallization process which is conducted in at least one first crystallization unit (10) and in at least one second crystallization unit (18), wherein in a first process cycle an enantiomer is crystallized in the first crystallization unit (10) and a racemic compound is crystallized in the second crystallization unit (18), wherein in a second process cycle the enantiomer is crystallized in the second crystallization unit (18) and the racemic compound is crystallized in the first crystallization unit (10), wherein during each process cycle in at least one process sub-step (B?C, F?G) a mother liquor (12) being contained in the first crystallization unit (10) is mutually exchanged with a mother liquor (20) being contained in the second crystallization unit (18). An auto-seeding process sub-step is applied at the beginning of a process cycle.

Abstract: The present invention provides a means for the rapid selection of optimum resolving agents and solvents, combinations and conditions to separate optical isomers. The present invention combinedly describes and automates a full lifecycle of chiral separation method development and optimization through a series of kits and procedures providing screening, automation for screening, racemate recovery, enantiomer preparation, and method optimization.

Abstract: High yields and purity are obtained in the purification of enantiomers of chiral carboxylic acids by preparative-scale chromatography by including a tertiary alcohol in the mobile phase in conjunction with an acidic modifier and a hydrophobic solvent. The tertiary alcohol is superior to other, more commonly used alcohols by reducing the extent of esterification of the enantiomer that otherwise lowers the yield and the purity.

Abstract: The invention relates to pure (R)-CMH and to the optical resolution of CMH-racemate, a key intermediate in the synthesis of (S)-Pregabalin. The invention also relates to the process for optically purifying (R)-CMH and to the process for isolating (S)-CMH from the mother liquor.

Abstract: Methods for racemate separation for compound-forming substances. In this method, at least one fraction which is enriched with an enantiomer is produced in one method step. Finally, a preferred crystallization is carried out on the fraction.

Abstract: Optically active diphenylalanine compounds may be conveniently prepared in a good yield by reacting a diphenylalanine compound represented by formula (1) with an optically active amine compound represented by formula (2) in the presence of an organic solvent to give a diastereomeric salt represented by formula (5) and then treating the diastereomeric salt under acidic conditions to give an optically active diphenylalanine compound represented by formula (3): wherein each symbol is as defined in the specification.

Abstract: The present invention provides a method for producing optically active flurbiprofen. The method of the present invention includes mixing racemic flurbiprofen and (S)- or (R)-3-methyl-2-phenylbutylamine in an organic solvent to produce a diastereomeric salt; and treating the diastereomeric salt with an acid in a second solvent. In the method of the present invention, flurbiprofen having a desired absolute configuration can be obtained very efficiently without repeating the procedure for optical resolution a plurality of times.

Abstract: A method of obtaining an enantioenriched organic compound comprising the steps of: 1) generating from a starting racemic, non-enantiopure or achiral compound a first mixture comprising at least one fluorous-tagged compound and at least one other non-fluorous tagged compound, at least one of these two compounds being enantioenriched relative to the starting compound; 2) contacting a first non-fluorous phase including the first mixture with a fluorous phase at a first phase interface, the fluorous-tagged compound distributing between the first non-fluorous phase and the fluorous phase; and 3) contacting the fluorous phase with a second non-fluorous phase at a second phase interface. The method further includes the step of having a third compound in the second non-fluorous phase that reacts with the fluorous-tagged compound to produce a second compound and the step of generating the first mixture by chemical or enzymatic kinetic resolution of a racemic or non-enantiopure compound.

Abstract: This invention is drawn to a process for the production of (R,R)-phenylisoserine or a 1–4C-alkyl ester thereof.

Abstract: The present invention relates to the field of organic synthesis and more particularly to a new process for the optical resolution of a precursor of sclareolide. This process includes the reaction of [(1RS,2RS,4aSR,8aSR)-2-hydroxy-2,5,5,8a-tetramethyldecahydronaphthalen-1-yl]acetic acid, or an alkaline salt thereof, with an enantiomer of the 2-(methylamino)-1-phenyl-1-propanol, or an ammonium salt thereof respectively, which is used as resolving agent.

Abstract: A method of crystallizing optically active mandelic acids characterized in that it comprises adding alkali to an aqueous solution comprising optically active mandelic acids and mineral acid for partial neutralization, and then crystallizing the optically active mandelic acids from the aforementioned aqueous solution.

Abstract: The present invention relates to a production method of (R)-3-hydroxy-3-(2-phenylethyl)hexanoic acid which comprises optical resolution of racemic 3-hydroxy-3-(2-phenylethyl)hexanoic acid with an optically active amine of the formula (VIII) 1

Abstract: The present invention includes a method for extracting bio-functional and bio-responsive fractions from biomass. The method includes providing biomass; treating the biomass with saturated steam at a time and temperature effective to extract bio-functional fractions; rapidly depressurizing the biomass and steam; mixing a depressurized bio-functional fraction with reagent that breaks down the fraction into oligomers and monomers; and separating the monomers from the each other and the oligomers using ion exchange.

Abstract: Diketo- and pyridine-containing chiral crown ligands having at least two chiral bulky groups attached to two different chiral carbon atoms of the crown that are covalently bonded to or coated on suitable solid supports, and further coated by hydrophobic organic solvents are disclosed. These compositions and associated methods are characterized by selectivity of several target amine or amino acid enantiomers over their counter-enantiomers and derivatives. The composition preferably has an &agr;-value greater than or equal to 4. This allows for the separation of such enantiomers with non-chromatographic resin bed separations of three separation stages or less.

Abstract: In a process comprising synthesizing pyranes including [R—(R*,R*)]-N-[3-[1-[5,6-dihydro-4-hydroxy-2-oxo-6-(2-phenylethyl)-6-propyl-2H-pyran-3-yl]propyl]phenyl]-5-(trifluoromethyl)-2-pyridinesulfonamide the present invention comprises the improvements comprising: (a) providing a racemic mixture of 3-hydroxy-3-(2-phenylethyl)-hexanoate ethyl acetate by reacting said 1-phenyl-hexan-3-one with ethylbromoacetate under Reformatsky conditions; and (b) separating (R)-3-hydroxy-3-(2-phenylethyl)-hexanoic acid in enantiomeric excess by saponification and reverse resolution of the racemate of step (a) to produce a resolved product. In addition, the present invention comprises a reverse resolution process for separating an enantiomer from a mixture of enantiomers.

Abstract: A stereoselectively method of preparing a 1,2-disubstituted cycloalkyl, such as aminocycloalkyl ether compounds, from a trans-1,2-disubstituted cycloalkyl or a cis-2-substituted cycloalkanol. For example, a stereoselective method of preparing 1R-(3R-hydroxypyrrolidin-1-yl)-2R-(2-phenylethoxy)-cyclohexane from 1R,2R-cyclohexanediol or from meso-cis-1,2-cyclohexanediol is described. Aminocycloalkyl ethers, such as 1R-(3R-hydroxypyrrolidin-1-yl)-2R-(2-phenylethoxy)-cyclohexane, can be used to treat cardiac disease.

Abstract: A method of obtaining an enantioenriched organic compound comprising the steps of: 1) generating from a starting racemic, non-enantiopure or achiral compound a first mixture comprising at least one fluorous-tagged compound and at least one other non-fluorous tagged compound, at least one of these two compounds being enantioenriched relative to the starting compound; 2) contacting a first non-fluorous phase including the first mixture with a fluorous phase at a first phase interface, the fluorous-tagged compound distributing between the first non-fluorous phase and the fluorous phase; and 3) contacting the fluorous phase with a second non-fluorous phase at a second phase interface. The method further includes the step of having a third compound in the second non-fluorous phase that reacts with the fluorous-tagged compound to produce a second compound and the step of generating the first mixture by chemical or enzymatic kinetic resolution of a racemic or non-enantiopure compound.

Abstract: Methods for the separation of chaotropic and kosmotropic enantiomers within a racemic mixture are provided. Such methods comprise differentially partitioning the enantiomers into stabilized microdomains of low density water and high density water abutting a porous surface.

Abstract: A process for racemate resolution of 2-hydroxypropionic acids by reacting the racemic acid with an optically active base and subsequently separating off a diastereomeric salt of acid and base comprises using 1-(4-chlorophenyl)ethylamine as optically active base.

Abstract: A method is provided for processing a solution having optical isomers to obtain a (2R,3S) target isomer: 1

Abstract: A method and workstation for optimizing separation of a given racemate automation technology, and computer-controlled design is disclosed. The workstation includes a synthesizer, an analyzer, a robot and computer in communication with the synthesizer and analyzer. The computer includes one or more programs for regulating variables such as types of stationary phases; types of solvents; amounts of solvents; pressure; temperature; and employs methods for optimizing separation of a given racemate and for designing optimized experiments for further investigation.

Abstract: (±)-&agr;-(Difluoromethyl)-ornithine is separate into its isomers using (−)-O,O′-di-p-toluoyl-L-tartaric acid. (−)-&agr;-(Difluoromethyl)-ornithine monohydrochloride monohydrate and in particular the (−)-isomer are inhibitors of ornithine decarboxylase and thereby have numerous pharmacological actions.

Abstract: The present invention relates to a method of preparing a 1-nitro-3-substituted-3-amino-2-propanol diastereomer represented by Structural Formula I: In Structural Formula I, R is an amine protecting group, and R1 is an amino acid side-chain, a protected amino acid side-chain, a substituted or unsubstituted aliphatic group, a substituted or unsubstituted aromatic group, a substituted or unsubstituted heteroaromatic group, a substituted or unsubstituted aralkyl or a substituted or unsubstituted heteroaralkyl group. The method involves contacting a 1-nitro-3-substituted-3-amino-2-propanone with a reducing agent to form a mixture of 1-nitro-3-substituted-3-amino-2-propanol diastereomers. The 1-nitro-3-substituted-3-amino-2-propanol diastereomers are then separated by simulated moving bed chromatography to obtain one or more 1-nitro-3-substituted-3-amino-2-propanol diastereomer.

Abstract: Improved processes for preparation of high enantiomeric purity compounds center on resolution using simulated moving bed chromatography of a racemic precursor early in the synthesis. Resolution is effected with high enantiomeric purity, and subsequent reactions of the desired enantiomer performed with high optical specificity to maintain enantiomeric purity. The undesired enantiomer is racemized and recycled to the resolution phase to avoid loss.

Abstract: There is provided a process for industrially and efficiently producing an optically active N-protected-N-methyl-4-halogenophenylalanine at a high purity, which is useful as an intermediate for the production of pharmaceutical agents. An optically active N-protected-N-methyl-4-halogenophenylalanine (including the free form and/or the salt form thereof) purified to a high purity is produced by way of the deposition and isolation in the form of salt (DCHA salt or the like) from an optically active N-protected-N-methyl-4-halogenophenylalanine containing at least the optical isomer thereof as an impurity. Because the intended compound at a high purity can be recovered and obtained at a high yield, the process of the present invention is very useful as a process for producing the intermediate for the production of pharmaceutical agents.

Abstract: Disclosed a process for preparing substantially enantiomerically pure 3-amino-3-cyclopropylpropanoate esters, i.e., esters of 3-amino-3-cyclopropylpropanoic acid (3-cyclopropylalanine esters or 3-CPA esters) by a 5-step process wherein cyclopropanecarboxaldehyde (CPCA) is reacted with malonic acid and a source of ammonia to obtain 3-cyclopropylalanine (3-CPA); esterifying the 3-CPA; contacting the 3-CPA ester with a substantially enantiomerically pure acid selected from tartaric acid, dibenzoyltartaric acid and mandelic acid to obtain a diastereomeric salt of the 3-CPA ester and the acid; recrystallization of the salt to substantial diastereomeric purity; and neutralizing the salt to afford the substantially enantiomerically pure 3-CPA ester.

Abstract: A process for the preparation of carbocyclic stereoisomers of formulae (I), (I'), (IIA'), (IIB'), (VA') and (VB'), including enantiomerically pure (IIA'), (I) and (I') utilizing fractional crystallization of salts formed with a chiral base; a reducing agent; a protecting group removing agent or a protecting group providing agent.

Abstract: A process for preparing optically active 2-hydroxymethyl-3-phenylpropionic acid by resolving (RS)-2-hydroxymethyl-3-phenylpropionic acid via crystallization of an optically active amine salt, where the amine is optically active cis-1-amino-2-indanol salt, optically active .alpha.-methylbenzylamine salt, or optically active 3-methyl-2-phenyl-1-butylamine salt.

Abstract: A process for the preparation of optically active phenylcyclohexylglycolate esters is described. The process utilizes carboxylic acid activation to couple (R)-- or (S)-cyclohexylphenylglycolic acid (CHPGA) with 4-N,N-diethylamino butynol or other propargyl alcohol derivatives. The preparation of the hydrochloride salt is also described. In addition, a resolution process employing tyrosine methyl ester enantiomers for preparing a single enantiomer of CHPGA from racemic CHPGA is disclosed.

Abstract: An object of the present invention is to provide a process for producing a .beta.-amino-.alpha.-hydroxy acid derivative via efficient and industrially utilizable steps.The present invention provides a process for producing a .beta.-amino-.alpha.-hydroxy acid derivative represented by the general formula (2) given below which comprises hydrolyzing an .alpha.-amino-.alpha.', .alpha.-dihaloketone derivative of the general formula (1) given below in the presence of a base, followed by protecting the amino group or without protecting the same.

Abstract: A method for producing an optically active amino acid or derivative thereof having a high optical purity from an optically active amino acid comprising optical isomers or derivative thereof, which comprises any one of processes (A), (B), and (C), wherein the process (A) comprises the steps: (1) previously preparing an optically active amino acid or derivative thereof having an optical purity higher than a convergent value of a mutual solubility of the optical isomers and (2) crystallizing the optically active amino acid or the derivative thereof that exists in excess, said convergent value being a ratio of the desired optical isomer in the optical isomers dissolved in a mother liquor in which crystals of a racemate and an optically active compound coexist at equilibrium (the optical purity in a mother liquor). The processes (B) and (C) are described in the specification.

Abstract: Described herein is a novel process to resolve a racemic compound into its optically active isomers without need for chemical transformation such as salt formation. The process advantageously utilizes polymers containing chiral moieties in their repeat units as well as exhibiting critical solution temperature behavior in a suitable solvent. An embodiment describes the resolution of tryptophan.

Abstract: Synthetic mammalian matrix metalloprotease inhibitors are disclosed that are useful for treating or preventing diseases wherein said diseases are caused by unwanted mammalian matrix metalloprotease activity and include skin disorders, keratoconus, restenosis, rheumatoid arthritis, wounds, cancer, angiogenesis and shock.

Abstract: A process for the preparation of 2-(2-fluoro-4-biphenyl)propianic acid enantiomers comprising a II order resolution of ketals of formula ##STR1## wherein R.sub.1 ad R.sub.2 have the meanings reported in the description; the asterisk shows the chiral carbon atom and the asymmetric carbon atoms marked by .alpha. and .beta. have both R or S configuration is described.

Abstract: A process for preparing an optically active 1,4-bridged-cyclohexane carboxylic acid derivatives which are clinically important thromboxane A.sub.2 thromboxane of formula (IV): ##STR1## wherein, R is phenyl or phenyl substituted with hydroxy, lower alkoxy, halogen, or lower alkyl; Y is oxygen, methylene, substituted methylene; m is 0 or 1; n is 0, 1 or 2; q is 3 or 4 with the proviso that when m is 1, n is 0 or 1 from an optically active norbornyl amine derivative.

Abstract: Described herein is a novel process to resolve a racemic compound into its optically active isomers without need for chemical transformation such as salt formation. The process advantageously utilizes polymers containing chiral moieties in their repeat units as well as exhibiting critical solution temperature behavior in a suitable solvent. An embodiment describes the resolution of tryptophan.

Abstract: Novel trienoic compounds having activity for retinoic acid receptors and retinoid X receptors are provided. Also provided are pharmaceutical compositions incorporating such compounds and methods for their use.

Abstract: The present invention provides three optical resolution methods. The first aspect comprises the steps of adding an optically active bifunctional resolving reagent to a bifunctional compound to form a liquid material, precipitating crystals therefrom, and treating the crystals and the liquid material separately with an acidic material, a basic material, or a basic material and an acidic material, to obtain a pair of enantiomers of an optically active bifunctional compound. The second aspect comprises an optical resolution method by which one necessary enantiomer of a pair of enantiomers in an optically active bifunctional compound is exclusively obtained. The third aspect comprises a method for racemizing one unnecessary enantiomer of a pair of enantiomers in an optically active bifunctional compound which is formed by the optical resolution method of the present invention.