A new isoquinolinone derivative with noble vasorelaxation activity.

The pharmacological effects of BDPBI (7-bromo-1,4-dihydro-2-phenyl-4,4-bis(4-pyridinylmethyl)2H-isoquinolin-3-one dihydrochloride) were tested on isolated endothelium-containing or denuded aorta of the guinea pig. BDPBI with the formula C(27)H(24)BrCl(2)N(3)O was synthesized starting with 3-isochromanone. In the endothelium-containing preparations of the aortic rings, phenylephrine (PHE; 10 micromol/l) elicited contracture and acetylcholine (ACh; 10 micromol/l) or BDPBI (0.