Alfalfa (Medicago sativa L.) flavonoids. 1. Apigenin and luteolin glycosides from aerial parts

Nine flavones and adenosine have been identified in aerial parts of alfalfa , and their structures were established by spectral (FABMS and NMR) techniq ues. Five of the identified compounds, including apigenin 7-O-[beta -D-gluc uronopyranosyl(1-->2)-O-beta -D-glucuronopyranosyl]-4'-O-beta -D-glucuronop yranoside, apigenin 7-O-[2-O-feruloyl-beta -D-glucuronopyranosyl(1-->2)-O-b eta -D-glucuronopyranosyl]-4'-O-beta -D-glucuronopyranoside, apigenin 7-O-{ 2-O-feruloyl-[beta -D-glucuronopyranosyl(1-->3)]-O-beta -D-glucuronopyranos yl( 1-->2)-O-beta -D-glucuronopyranoside}, apigenin 7-O-{2-O-p-coumaroyl-[b eta -D-glucuronopyranosyl(1-->3)]-O-beta -D-glucuronopyranosyl(1-->2)-O-bet a -D-glucuronopyranoside}, and luteolin 7-O-[2-O -feruloyl-beta -D-glucuron opyranosyl(1-->2)-O-beta -D-glucuronopyranosyl]-4'-O-beta -D-glucuronopyran oside, have not been reported before in the plant kingdom. Additionally, fi ve known compounds, including apigenin 7-O-beta -D-glucuronopyranoside, api genin 4'-O-beta -D-glucuronopyranoside, apigenin 7-O-[beta -D-glucuronopyra nosyl(1-->2)-O-beta -D-glucuronopyranoside], luteolin 7-O-beta -D-glucurono pyranoside, and adenosine, were identified.