[Alkyl- and alkoxy-substituted lamtidine analogs: synthesis and H2-antagonistic activity. 38. H2-antihistaminics].

In studies on the structure-activity relationships of histamine H2-receptor antagonists, lamtidine analogous derivatives of ortho-, meta- und para-substituted piperidinomethylphenoxypropylamines bearing an additional substituent on the aromatic ring were prepared and tested for their H2-antagonistic activity on the isolated guinea-pig atrium. An additional substituent decreases the H2-antagonistic activity of the 3-(3-piperidinomethyl-phenoxy)-propylamine derivatives, while 2-membered substituents neighboring the connecting chain increase the activity of the ortho- and para-piperidinomethyl-substituted phenoxypropylamine derivatives.