A new series of antiarrhythmic procainamide derivatives: toxicity and activity-simulated passive absorption relation.

Several compounds derived from benzamidines and nicotinic pyridinic amidines with a structure similar to that of procainamide, exhibit notable antiarrhythmic properties after injection into animals. The diffusion rate of these different compounds through a solid lipidic artificial membrane was studied with Dibbern's apparatus. A statistical relation was established between the diffusion rate and the principal pharmacological parameters obtained after intraperitoneal injection (toxicity and anthiarrhythmic activity). Essential structural elements seem to determine a better bioavailability than procainamide: character of the substitution (in para) of the benzenic cycle; length of the lateral chain.