Patent ID: 6114163
Filing Date: 2000-09-05
Classification: C07C,C12P

Abstract:
A process for obtaining an optically active L-alpha-amino acid from the corresponding racemic D,L-alpha-aminocarboxylic acids comprising the steps ofa) chemically acylating the said D,L-alpha-aminocarboxylic acids to produce N-Acetyl-D,L-alpha-aminocarboxylic acids;b) adding sufficient base to bring said N-Acetyl-D,L-alpha-aminocarboxylic acids to a pH range of between about 6 and 8 and preferentially deacylating the N-Acetyl-L-alpha-aminocarboxylic acid present in the mixture using a stereo specific acylase to form a composition comprising L-alpha-aminocarboxylic acid, an equimolar amount thereto of acetate, N-Acetyl-D-alpha-aminocarboxylic acid salt and a lesser amount of N-Acetyl-L-alpha-aminocarboxylic acid salt;c) separating the composition formed in step (b) into a first fraction containing most of the L-alpha-aminocarboxylic acid and a second fraction comprising N-Acetyl-D-alpha-aminocarboxylic acid salt and an amount of acetate equivalent to the L-alpha-aminocarboxylic acid formedd) adding to said second fraction an amount of N-Acetyl-D,L-alpha-aminocarboxylic acid equivalent to the removed L-alpha-aminocarboxylic acid, then removing the acetic acid formed by distillation;e) racemizing the mixture of step (d);f) subjecting the racemized mixture to the specific deacylation procedure of step (b).