Preparation and local anesthetic activity of benzotriazinone and benzoyltriazole derivatives.

Two sets of benzotriazinone and benzoyltriazole derivs. were prepd. and tested for local anesthetic activity in comparison with lidocaine. Several of the prepd. compds. exhibited a fairly good activity comparable or superior to that of lidocaine. The presence of a benzotriazinone or a benzoyltriazole moiety as an arom. system was quite profitable for both the intensity and duration of activity. The acute toxicity in mice of the four most potent compds. of the series was also assessed. Compd. I, which has an anesthetic activity comparable to that of lidocaine, was also characterized by a more favorable therapeutic index. All compds. were tested in vitro to evaluate their neg. chronotropic action in isolated rat right atria.