Process for the preparation of 9-hydrazono-6,7,8,9-tetrahydro-4H-pyro[1,2-a]pyrimidine-4-one compounds, the salts and hydrates thereof

摘要

A process for the preparation of nitrogen bridgehead condensed pyrimidine compounds of the general formula <IMAGE> I [wherein R represents hydrogen or lower alkyl; R1 represents hydrogen, lower alkyl, carboxy or a derivative thereof or styryl; R2 represents hydrogen or optionally substituted lower alkyl; R3 represents hydrogen, optionally substituted lower alkyl, aryl, aralkyl, halogen, carboxy or a derivative thereof, the group -(CH2)m-COOH (in which m is the integer 1, 2 or 3) or a carboxy derivative thereof, formyl, lower alkanoyl or a condensed thereof; R4 represents hydrogen, optionally substituted alkyl, aryl optionally substituted by one or more substituents, optionally substituted aralkyl, a heterocyclic group optionally substituted by one or more substituents, the group (CH2)m-Het (in which m is the integer 1, 2 or 3; Het is an optionally substituted heterocyclic group); R5 represents hydrogen, C1-6alkyl, aryl optionally substituted by one or more substituents, formyl, lower alkanoyl, optionally substituted aroyl or heteroaryl; or R4 and R5 together with the nitrogen therebetween represent an optionally substituted mono- or bicyclic heterocyclic ring optionally containing further heteroatom] and pharmaceutically acceptable salts, hydrates, stereoisomers, optically active isomers, geometrical isomers and tautomers thereof.