Process for the resolution of the racemate S-(carboxymethyl)-(RS)-cysteine (A)
Process for the separation of the racemate (R,S)-cysteine
Optical resolution process for DL-cysteine
Optical resolution of DL-cysteine Patent #: 4621151
ApplicationNo. 06/892059 filed on 08/01/1986
US Classes:562/401, Racemization or separation of optical isomers548/201, The -C(=X)- is part of a -C(=X)X- group, wherein the X's are the same or diverse chalcogens562/557, Alpha N, beta S - acids or salts thereof564/304Of benzene ring containing compounds
ExaminersPrimary: Lone, Werren B.
Assistant: Clarke, Vera C.
Attorney, Agent or Firm
International ClassesC07D 277/06 (20060101)
C07D 277/00 (20060101)
Foreign Application Priority Data1985-08-06 JP
AbstractMethod for optical resolution of DL-cysteine by (1) reacting DL-cysteine with formaldehyde to prepare DL-thiazolidine-4-carboxylic acid (DL-TCA), (2) forming diastereomer salts of D-TCA and of L-TCA by reacting DL-TCA with an optically active 1-(1-naphthyl)ethylamine, (3) separating said diastereomer salts by difference of the solubilities thereof in a solvent, (4) recovering D-TCA from said diastereomer salt of D-TCA and finally obtain D-cysteine, and recovering L-TCA from said diastereomer salt of L-TCA and finally obtain L-cysteine.Method for optical resolution of (R,S)-1-(1-naphthyl)ethylamine (R,S)-NEA by (1) reacting an optically active cysteine with formaldehyde to prepare an optically active thiazolidine-4-carboxylic acid, (2) forming diastereomer salts of (R)-NEA and of (S)-NEA by reacting (R,S)-NEA with optically active thiazolidine-4-carboxylic acid, (3) separating said diastereomer salts of (R)-NEA and of (S)-NEA by difference of the solubilities thereof in a solvent, (4) recovering (R)-NEA from said diastereomer salt of (R)-NEA, and recovering (S)-NEA from said diastereomer salt of (S)-NEA.
Field of SearchRacemization or separation of optical isomers