Class / Patent application number | Description | Number of patent applications / Date published |
562401000 | Racemization or separation of optical isomers | 18 |
20080287704 | PREPARATIVE-SCALE SEPARATION OF ENANTIOMERS OF CHIRAL CARBOXYLIC ACIDS - 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. | 11-20-2008 |
20090253932 | Resolution of Racemic Organic Acids with (1S, 4S)-4[3,4-Dichlorophenyl]-1,2,3,4-Tetrahydro-N-Methyl-1-Naphthaloneamine - The present invention relates to novel chiral resolving agents and a process for resolution of racemic organic acids and their derivatives of the formula (+, −)—R | 10-08-2009 |
20100022798 | Ibuprofen amine salts and synthesis thereof - The present invention discloses an ibuprofen amine salt and the synthesis thereof, and more particularly an ibuprofen amine salt yielded by the neutralization reaction of a racemic mixture of ibuprofen with tris(hydroxymethyl)aminomethane in a solution system of water and an organic solvent. Compared with racemic mixtures of ibuprofen, the ibuprofen amine salt has higher solubility and a higher melting point, thereby having better bioavailability and properties than racemic mixtures of ibuprofen during pharmaceutical processing. Further, the ibuprofen amine salts of the present invention are stable between pH 4 and 9 so that they can be more widely applied to medicines. | 01-28-2010 |
20100312010 | Process for the Preparation of (S)-Pregabalin - The present invention provides a process for resolving racemic pregabalin to S-pregabalin by using a chiral acid to form a pregabalin salt, purifying the salt to obtain a purified S- pregabalin salt then neutralizing the salt to obtain S-pregabalin having good chiral purity. | 12-09-2010 |
20110092732 | APPLICATION OF IRIDIUM COMPLEXES IN ASYMMETRIC CATALYTIC HYDROGENATION OF UNSATURATED CARBOXYLIC ACIDS - The present invention relates to a preparation method of carboxylic acids with optical activity, particularly, publishes that very useful chiral carboxylic acids can be obtained by the asymmetric catalytic hydrogenation of tri-substituted α,β-unsaturated carboxylic acids, with the complexes of the chiral phosphor nitrogen ligands and iridium used as the catalysts which show high activity and enantioselectivity (up to 99.8% ee), thus provides a more efficient method with higher enantioselectivity for asymmetric catalytic hydrogenation of chiral carboxylic acid-like compounds, and has important application value to asymmetric hydrogenation of chiral carboxylic acids. | 04-21-2011 |
20110098502 | NEW PROCESS FOR RESOLVING S-3- (AMINOMETHYL)-5-METHYLHEXANOIC ACID - The present invention relates to a process for resolving S-3-(Aminomethyl)-5-methylhexanoic acid, which adopts benzoyl-L-glutamic acid, 4-methyl benzoyl-L-glutamic acid, benzene sulfonyl-L-glutamic acid or 4-methyl benzene sulfonyl-L-glutamic acid as a resolution agent to make a first resolution to racemic 3-aminomethyl-5-methylhexanoic acid, and adopts the resolution agent same to that of the first resolution to make a second resolution to the first resolution product to obtain the second resolution product, thus the resolution salt product is obtained, and further hydrolyzed by an acid, the resolution agent is extracted to be separated, the pH is adjusted to be neutral, the product S-3-(Aminomethyl)-5-methylhexanoic acid, i.e. the pregabalin, is then precipitated by distillation, therefore the present invention has the characteristics of polluting the environment slightly, high efficiency and stability, simpleness and practicality, producing product with high purity and a low sproduction cost, and is suitable for large-scale production. | 04-28-2011 |
20110124909 | NOVEL PROCESS - The present invention relates to a novel process of preparing an enantiomerically enriched γ-amino acid, such as enantiomerically enriched (S)-pregabalin. | 05-26-2011 |
20110144383 | PROCESS FOR PREPARING (S)-3-(AMINOMETHYL)-5-METHYLHEXANOIC ACID - Disclosed herein is a process for the preparing (S)-3-(aminomethyl)-5-methylhexanoic acid by optical resolution of (±)-3-(aminomethyl)-5-methylhexanoic acid and a resolving agent employing a suitable solvent. | 06-16-2011 |
20110172460 | PROCESS FOR THE MANUFACTURE OF RACEMIC 2-ARYL-PROPIONIC ACID - There is described a process for the manufacture of a racemic 2-aryl propionic acid compound, or a pharmaceutically acceptable salt thereof, which comprises reacting the S- or R-enantiomer of the corresponding 2-aryl propionic acid compound with a base. | 07-14-2011 |
20120016157 | METHOD FOR OBTAINING OPTICALLY PURE AMINO ACIDS - This invention relates to a method for obtaining optically pure amino acids, including optical resolution and optical conversion. This method significantly shortens the time taken for optical transformation, and enables the repeated use of an organic solution containing a enantioselective receptor, to thereby obtain optically pure amino acids in a simple and remarkably efficient manner, and to enable the very economical mass production of optically pure amino acids. | 01-19-2012 |
20120220799 | NOVEL PROCESS - The present invention relates to a novel process for the preparation of γ-amino acids, such as (±)-3-(aminomethyl)-5-methyl-hexanoic acid 1, which is a key intermediate in the preparation of the potent anticonvulsant pregabalin, (S)-(+)-3-(aminomethyl)-5-methyl-hexanoic acid 2. | 08-30-2012 |
20140323758 | NOVEL PROCESS FOR RACEMIZATION OF AN OPTICALLY ACTIVE (S)-3-CARBAMOYLMETHYL-5-METHYL-HEXANOIC ACID TO CORRESPONDING 3-CARBAMOYLMETHYL-5-METHYL-HEXANOIC ACID RACEMATE - A novel process for racemization of (S)-3-carbamoylmethyl-5-methyl-hexanoic acid to 3-carbamoylmethyl-5-methyl-hexanoic acid racemate has been developed. | 10-30-2014 |
20160039743 | COMPOUND, OPTICAL RESOLUTION METHOD, AND DERIVATIVE OF AN OPTICAL ISOMER OF AN AMINO ACID - Disclosed is a compound represented by chemical formula ( | 02-11-2016 |
20170233334 | METHOD FOR PREPARING D-ARGININE | 08-17-2017 |
562402000 | Physical resolution | 4 |
20080207944 | Method For Separating Compound-Forming Chiral Systems - 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. | 08-28-2008 |
20120197040 | Method for separation of racemic compound-forming chiral substances by a cyclic crystallization process and a crystallization device - 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 ( | 08-02-2012 |
20120245379 | PROCESS FOR THE PREPARATION OF ENANTIOMERICALLY PURE tert-LEUCINE - 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. | 09-27-2012 |
20130184489 | Method for Separation of Racemic Compound-Forming Chiral Substances by a Cyclic-Crystallization Process and a Crystallization Device - 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 ( | 07-18-2013 |