Olean-12-en-28-oicacid, 3-[(6-deoxy-4-O-D-xylopyranosyl-L-mannopyranosyl)oxy]-16-hydroxy-,O-D-glucopyranosyl-(1®4)-O-6-deoxy-L-mannopyranosyl-(1®2)-L-arabinopyranosyl ester, (3b,16a)-