Saponin and Sapogenol. XXXIX. Structure of Soyasaponin A1, a Bisdesmoside of Soyasapogenol A, from Soybean, the Seeds of Glycine max Merrill

Abstract

Five bioactive triterpene-oligoglycosides, named soyasaponins I, II, III, A1(3), and A2(2), were isolated from soybean, the seeds of Glycine max Merrill (Leguminosae). By employing a photochemical degradation method and a lead tetraacetate degradation method, which are two of four selective cleavage methods available for the glucuronide linkage in oligoglycosides, the structure of soyasaponin A1was elucidated to be 3-O[β-D-glucopyranosyl(l →2)-β-D-galactopy-ranosyl(l →2)-β-D-glucuronopyranosyl-22-O-[β-D-glucopyranosyl(l→3)-α-L-arabinopyranosyl]-soyasapogenol A (3). © 1985, The Pharmaceutical Society of Japan. All rights reserved.