Abstract: Changrolin, a quinazoline derivative, is one of the most effective drugs in the treatment of paroxysmal ventricular tachycardia and ventricular premature beats in clinical trial but with some side effects.In an attempt to search for new antiarrhythmic agents superior to changrolin, a series of Mannich bases derived from various aromatic or heterocyclic compounds was synthesized.These compounds were prepared by condensation of the corresponding chlorocompounds with p-aminophenol and the resulting intermediates reactedwith formaldehyde and various amines to give the different Mannich bases.Compounds 9, 12, 13,30 and 33 exhibited protective effects against experimental arrythmias induced by aconitine, among them compounds 9,12 and 13 were found to be comparatively safe and effective. Detailed results of pharmacological tests will be published elsewhere.