NOVEL 4,7-DIHYDROISOTHIAZOLO(5,4-B)PYRIDINE DERIVATIVE, PRODUCTION THEREOF AND MEDICINE FOR CIRCULATORY ORGAN CONTAINING SAID DERIVATIVE AS ACTIVE INGREDIENT

摘要

NEW MATERIAL:A compound expressed by formula I [R<1> represents H, OH, benzyloxy, lower alkoxy, etc.; R<2> represents (substituted)alkyl; m is 1-3] or acid addition salt thereof. EXAMPLE:Ethyl-3-benzyloxymethyl-6-methyl-4-(3-nitrophenyl)-4, 7-dihydroisothia zolo[5,4-b]pyridine-5-carboxylate. USE:A remedy for cardiovascular system diseases such as hypotensor, blood stream enhansor, total peripheral vasculary resistance reducer, etc., which has strong calcium antagonism. PREPARATION:A 5-aminoisothiazole derivative expressed by formula II (R<6> represents OH, benzyloxy or lower alkoxy) is reacted with an alpha,beta-unsaturated ketone derivative expressed by formula III preferably in an inert solvent such as methanol in an inert atmosphere at 60-100 deg.C for several hr - several days.