11α,12β-Acetonyltenacissoside F acetone solvate: a new polyoxypregnane glycoside from the stems ofMarsdenia tenacissima

Abstract

The title compound (11 alpha, 12 beta-acetonyltenacigenin B 3-O-6-deoxy-3-O-methyl-beta-D-allopyranosyl-(1 -> 4)-beta-D-oleandropyranoside acetone solvate), C38H60O12 center dot C3H6O, was isolated from the stems of Marsdenia tenacissima. It contains five six-membered rings in chair and distorted half-chair conformations, two five-membered rings exhibiting envelope conformations and a three-membered ring. The unit cell (the asymmetric unit) also contains a disordered acetone molecule. The molecules are linked by two intermolecular O-(HO)-O-... hydrogen-bonds.