| abstract |
Two optically active amino acid-mandelic acid complexes are obtained by interacting in a solvent under pH conditions of 1.0-4.0 an amino acid expressed by a general formula <IMAGE> (in which R represents a methyl group, an ethyl group or a methylthioethyl group) and mandelic acid, one of the acids being an optically active substance and the other being a racemic modification, and optically resolving the resulting complexes into two diastereoisomers by using solubility difference therebetween. The optically active complexes are each decomposed by means of an acid, a strongly acidic ion-exchange resin, or a weakly basis ion-exchange resin to obtain optically active amino acids or optically active mandelic acid. |