Structure-activity relationship studies in the field of calcium antagonists. Xanthone 1,4-dihydropyridines bearing a 2,3-lactone ring

A series of xanthone 1,4-dihydropyridine derivatives bearing a 2,3-lactone ring and a 2-acetoxymethyl group were prepared. The compounds were evaluated for inotropic, chronotropic and calcium antagonist properties. The introduction of a 2,3-lactone ring improved the negative inotropic activity and selectivity.