Cardenolide and bufadienolide derivs - with positive inotropic active

摘要

Title cpds. of formula (I): (where R is the butenolide or alpha-pyrone ring; C3---C4 is a single or double bond, and A-B is which are cardioactive cpds. having positive inotropic activity at low dosage with favourable therapeutic index, are prepd. by treating 3-keto-4,5 beta-epoxy-steroids of formula (II): with hydrazine and opt. reducing the double bond formed in the 3,4-posn.