Four new flavonol glycosides from the leaves of Astragalus caprinus

Four new flavonol 3-O-glycosides were isolated from the leaves of Astragalus caprinus. Their structures were elucidated by spectroscopic methods as rhamnocitrin-3-O-3-hydroxy-3-methylglutaroyl(1-->6)]beta-D-apiofuranosyl(1-->2)]-beta-D-galactopyranoside (1), rhamnetin-3-O-3-hydroxy-3-methylglutaroyl(1-->6)]beta-D-apiofuranosyl(1-->2)]-beta-D-galactopyranoside (2), kaempferol-3-O-beta-D-xylopyranosyl(1-->3)-alpha-L-rhamnopyranosyl(1-->6)]-beta-D-galactopyranoside (3), and quercetin-3-O-beta-D-xylopyranosyl(1-->3)-alpha-L-rhamnopyranosyl(1-->6)]beta-D-apiofuranosyl(1-->2)]-beta-D-galactopyranoside (4).