METHOD OF PRODUCING (4S)-4-(4-CYANO-2-METHOXYPHENYL)-5-ETHOXY-2,8-DIMETHYL-1,4-DIHYDRO-1,6-NAPHTHYRIDINE-3-CARBOXAMIDE AND PURIFICATION THEREOF FOR USE AS PHARMACEUTICAL BIOLOGICALLY ACTIVE SUBSTANCE Russian patent published in 2021 - IPC C07D471/04 

FIELD: organic chemistry.

SUBSTANCE: invention relates to a method of producing compound (4S)-4-(4-cyano-2-methoxyphenyl)-5-ethoxy-2,8-dimethyl-1,4-dihydro-1,6-naphthyridin-3-carboxamide of formula (I), characterized in that the racemic compound of formula (XIII) is divided into corresponding enantiomers, wherein the compound of formula (XIII) is obtained by reacting a compound of formula (XVIII) with an orthoester of formula (XX), in which R denotes hydrogen or methyl, with acid catalysis and temperature of 100–120 °C. Invention also relates to compounds of formulas (XVIII) and (XVI a,b), use thereof in a method of producing a compound of formula (I), methods of producing compounds of formulas (XVIII), (XVI a,b) and (XIII).

EFFECT: novel method of producing a compound of formula (I), useful as a non-steroidal mineralocorticoid receptor antagonist, characterized by high overall output and purity of target compound and low production costs.

12 cl, 8 ex