A New Triterpenoidal Saponin from the Bark of Guaiacum officinale L.

Abstract

A new triterpenoidal saponin, akebonic acid-3-O-[α-L-rhamnopyranosyl-(1→3)-β-D-glucopyranosyl-( l→3)-α-L-rhamnopyranosyl-(l→2)-β-L-arabinopyranoside], named as guaianin Q (1), was isolated from the n-butanolic extract of the bark of Guaiacum officinale L. The structure of 1 was established with the help of the comparative studies of ID and 2D 1H - 13C NMR methods, FABMS, alkaline and acid hydrolyses. In addition to 1, a number of known saponins were also isolated and reported from the same source.