Studies on the constituents of Gliricidia sepium (Leguminosae) leaves and roots: isolation and structure elucidation of new triterpenoid saponins and aromatic compounds.

Our research program on the Central American fooder plant Gliricidia sepium led to the discovery of two new triterpene saponins (1 and 2) and known aromatic compounds. The new compounds possess 3beta,21beta, 24-trihydroxy-22-oxoolean-12-ene as an aglycon. The oligosaccharide moiety linked to C-3 of the aglycon contained two pyranoses (glucuronic acid and xylose); in addition the glucose residue of both 1 and 2 is also linked to C-21. Structure elucidation of these new compounds through the extensive use of 1D and 2D NMR techniques have provided detailed information about the sapogenin and the saccharide chains, inclusive of sugar sequence and the position of glycosylation.