Synthesis of Anemoclemosides A and B, Two Saponins Isolated from Anemoclema glaucifolium

Abstract

Steroidal and triterpenoid saponins are attractive for their wide-ranging pharmacological properties. The triterpenoid saponins Anemoclemoside A and B are root constituents of the Chinese folk medicinal plant Anemoclema glaucifolium (Ranunculaceae). Both compounds feature an unusual cyclic acetal linkage to the carbohydrate l-arabinose in its open chain form rather than the typical glycosidic bond present in normal saponins. The straightforward and scalable syntheses of both saponins starting from l-arabinose as well as l-lyxose and l-rhamnose are described.