Polyhydroxy pregnanes from Dregea volubilis

Abstract Three new polyhydroxy pregnanes named dregealol ( 1 ), volubilogenone ( 2 ) and volubilol ( 3 ) were isolated from the flowers of Dregea volubilis , and their structures elucidated from extensive 2D NMR analysis. The structure of volubilol ( 3 ) was confirmed by X-ray crystallographic studies. The known pregnane derivatives drevogenin D, iso -drevogenin P and 17α-marsdenin were also isolated.