In the present study, fourteen derivatives comprising of 5-benzylidene-2-(phenylimino)-thiazolidin-4-one moiety were synthesized. The structures of synthesized compounds were established by elemental analysis, IR, (1)H NMR, (13)C NMR and mass spectral data and tested for electrocardiographic, antiarrhythmic and antihypertensive activities. Compound 11 was found to be most potent in this series. The pharmacological results suggested that, the antiarrhythmic effects of these compounds were related to their Ca(++) ion channel antagonistic properties, which are believed to be due to the presence of 5-benzilidine-2-(phenylimino)-thiazolidin-4-one moiety. The antihypertensive effect of β-blocker side chain is enhanced by the presence of less bulky aliphatic and heterocyclic tertiary amines.