Synthesis of 2-guanyl-4-(3-substituted-phenyl)thiazoles with potent histamine H2-antagonism activity

The syntheses of novel 2-guanyl-4-(3-substituted-phenyl)thiazoles showing potent histamine H 2 -antagonism activity is reported. The most potent compound is 17 where the substitution at the 3-position of the phenyl ring is an N-methylamidino function