METHOD FOR PREPARING (4S) -4- (4-CYANO-2-METHOXYPHENYL) -5-ETHOXY-2,8-DIMETHYL-1,4-DIHYDRO-1,6-NAPHTHYRIDINE-3-CARBOX AMIDOGENE RECOVERY (4S) 4- (4-CYANO-2-METHOXYPHENYL) -5-ETHOXY-2,8-DIMETHYL-1,4-DIHYDRO-1,6-NAPHTHYRIDINE-3-CARBOX AMIDE BY ELECTROCHEMICAL PROCEDURES

摘要

The present invention relates to a novel method for the preparation of (4S)-4-(4-cyano-2-methoxyphenyl)-5-ethoxy-2,8-dimethyl-1,4-dihydro-1-6-naphthyridine-3-carboxamide of the formula (I) and for the recovery of (4S)-4-(4-cyano-2-methoxyphenyl)-5-ethoxy-2,8-dimethyl-1,4-dihydro-1-6-naphthyridine-3-carboxamide of the formula (I) starting from (4R)-4-(4-cyano-2-methoxyphenyl)-5-ethoxy-2,8-dimethyl-1,4-dihydro-1,6-naphthyridine-3-carboxamide of the formula ent-(I).