Two New C21 Steroids from the Roots of Cynanchum Otophyllum

Abstract

Two new C21 steroids, 12β- O-acetyl-20- O-(2-methylbutyryl)-sarcostin and its 3- O-digitoxopyranoside (1-2) were isolated from the roots of Cynanchum otophyllum, together with three known steroids, namely deacetylmetaplexigenin (3), sarcostin (4), and kidjoranin 3 -O-β-D-digitoxopyranoside (5). The structures of the new steroids were established by spectroscopic and chemical methods, especially two-dimensional NMR techniques.