Physapubenolide and pubescenin, two new ergostane-type steroids from Physalis pubescens L. (Solanaceae)

Abstract

Structures of two new ergostane-type steroids which occur in the leaves of a variety of Physalis pubescens L. (Solanaceae) growing in India were established by spectral analysis and chemical transformations. Physapubenolide (2a) is (20S,22R)-15α-acetoxy-5β,6β-epoxy-4β,14β-dihydroxy-1-oxo-witha-2,24-dienolide. Pubescenin (6a) is (20S,22R)-24,25-epoxy-1α-hydroxy-3β-(O-β-D-glucopyranosyl) with-5-enolide.