Withanolides from Withania somnifera roots

Abstract

Two new and seven known withanolides along with β-sitosterol, stigmasterol, β-sitosterol glucoside, stigmasterol glucoside, α + β glucose were isolated from the roots of Withania somnifera. Among the known compounds, Viscosa lactone B, stigmasterol, stigmasterol glucoside and α+ β glucose are being reported from the roots of W. somnifera for the first time. One of the new compounds contained the rare 16β-acetoxy-17(20)-ene the other contained unusual 6α-hydroxy-5,7α-epoxy functional groups in the withasteroid skeleton. The structures were elucidated by spectroscopic methods and chemical transformations.