PROCESS FOR PRODUCING OPTICALLY ACTIVE BENZYLSUCCINIC ACID AND INTERMEDIATE THEREFOR

摘要

A process for producing the optically active benzylsuccinic acid represented by formula (III) (wherein the carbon atom indicated by (S) has the S configuration), which is useful as a starting material for the benzylsuccinic acid derivative represented by formula (I) and salts thereof which are useful as a diabetic remedy, from a mixture of corresponding optical isomers through optical resolution using as an optical resolving agent an organic amine selected among (R)-1-(1-naphthyl)ethylamine, (R)- alpha -methylbenzylamine, (S)-1-phenyl-2-(p-tolyl)ethylamine, and quinine; and salts of the optically active benzylsuccinic acid, useful in the method of optical resolution, with an organic amine selected among (R)-1-(1-naphthyl)ethylamine, (R)- alpha -methylbenzylamine, (S)-1-phenyl-2-(p-tolyl)ethylamine, and quinine. The optically active benzylsuccinic acid having a high optical purity and a high chemical purity can be efficiently obtained by the method of optical resolution.