A series of phenoxypropanolamines having a hydrazinopyridazinyl moiety was synthesized. Their hypotensive and β-blocking activities were evaluated after intravenous administration of the compounds to anethetized rats. Some of them exhibited both activities. In particular, compound 20k is a candidate for clinical use due to its hypotensive activity, equal to that of hydralazine, and its β-blocking activity, 2.7-fold more potent than that of propranolol.
