Cardiovascular hybrid drugs: New benzazepinone derivatives as bradycardic agents endowed with selective beta(1)-non-competitive antagonism

The synthesis and pharmacological profile of some hybrid compounds bearing both the benzazepinone moiety present in Zatebradine and typical P-blocker aryloxypropanolamine groups are described. The new compounds proved to be endowed with negative chronotropic and inotropic activity and are weak vasorelaxant agents. The cardiodepressant action is probably due to selective beta(1)-noncompetitive reversible antagonism. Both enantiomers of the most active compound 5c were synthesized and they showed a different cardiovascular profile, that is (+)-(R)-enantiomer displays affinity for cardiac beta(1)-adrenoceptors, while (-)-(S)-enantiomer shows specificity for vessel smooth muscle.