PROCESS FOR PRODUCING PURE ENANTIOMERS OF POLYSUBSTITUTED 1,4-DIHYDROPYRIDINES AND PHARMACEUTICAL COMPOSITIONS COMPRISING SAME

摘要

A process for the optical resolution of racemic 1,4-dihydropyridines, containing isothioureido groups. Salification of racemic isothioureas with optically active acids produces diasteroisomeric mixtures of isothiouronium salts, that, using conventional techniques, are separated in the individual components to give optically pure isothioureides of 1,4-dihydropyridines and salts thereof with conventional acids. Said optically pure 1,4-dihydropyridines can then be subjected to desulphuration and to different transformations to give other enantiomerically pure and therapeutically useful 1,4-dihydropyridines.