Transformation of 1, 4-Dihydropyridine Ring of Calcium Antagonist NZ-105 into Cyclohexenone Ring

Abstract

On hydrolysis of the calcium antagonist, 2-(N-benzyl-N-phenylamino)ethyl 5-(5, 5-dimethyl-2-oxo-1, 3, 2-dioxaphosphorinan-2-yl)-1, 4-dihydro-2, 6-dimethyl-4-(3-nitrophenyl)pyridine-3-carboxylate hydrochloride ethanol (NZ-105 1·HCl·EtOH) in 35% hydrochloric acid, the 1, 4-dihydropyridine ring was transformed to a cyclohexeone ring, affording the cyclohexenonephosphonates 2 and 3.