Medicagenic acid saponins from Aster batangensis

Two new medicagenic acid saponins, named asterbatanoside J and K, were isolated from the roots of Aster batangensis. On the basis of chemical and spectral studies especially 2D NMR including COSY, HETCOR, HMQC, HOHAHA, TOCSY, ROESY and HMBC techniques, their structures were established as 3-O-beta-D-glucopyranosyl-(1--> 6)-beta-D-glucopyranosyl-2 beta, 3 beta-dihydroxy-olean-12-en-23 alpha, 28-dioic acid- 28-O-alpha-L-arabinopyranosyl-(1-->3)-alpha-L- rhamnopyranosyl-(1-->2)-beta-D-fucopyranoside and 3-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl- medicagenic acid-28-O-beta-D-xylopyranosyl-(-->4)-[alpha-L- arabinopyranosyl-(1 -->3)-alpha-L-rhamnopyranosyl-(1-->2) -beta-D-fucopyranside, respectively.