Monodesmosidic saponins from Herniaria hirsuta.

Two new monodesmosidic saponins, herniaria saponins E and F, were isolated from the aerial parts of Herniaria hirsuta. On the basis of chemical and spectral evidence, their structures were established to be 2-O-acetyl medicagenic acid 28-O-beta-D-xylopyranosyl- (1-->4)-alpha-L-rhamnopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->6)]-be ta- D-glucopyranoside (herniaria saponin E, 1) and medicagenic acid 28-O-beta-D-xylopyranosyl(1-->4)-alpha-L- rhamnopyranosyl(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D- glucopyranosyl-(1-->6)]-beta-D-glucopyranoside (herniaria saponin F, compound 2).