Synthesis and pharmacological properties of cardenolides substituted at the butenolide part

Article abstract of DOI:10.1016/0040-4020(96)00753-3

Deprotonation of the digitoxigenin lactone moiety with NaH in N-methylpyrrolidone yields and enolate that reacts at the 21- or 22-position depending on the electrophile. Lactone substituted derivatives of digitoxigenin have been prepared and their inhibition of the cardiac Na⁺ pump and the inotropic effect of some of the compounds have been studied. Structure-activity relationships are discussed in terms of the Holtje-Anzali model.