Effects of 3-alkylamino-7-chloro-4H-pyrido[2,3-e]-1,2,4-thiadiazine 1,1-dioxides on smooth muscle contractile activity

Abstract

New 3-alkylaminopyridothiadiazine dioxides have been synthesized and characterized in a search for more efficient and selective KATP-channel activators. The new compounds induced concentration-dependent relaxation of vascular (aorta) and gastrointestinal (ileum) smooth muscle. The pharmacological profiles of the new compounds were different from those of diazoxide or pinacidil but similar to that of verapamil. The results suggest that the myorelaxant properties of the new compounds depend on their capacity to reduce calcium inflow into smooth muscle cells.