New flavonoid glycoside from Vicia faba L.

Kaempferol 4´-O-α-rhamnopyranosyl-3-O-α-rhamnopyranosyl-(1→6)-β- glucopyranoside (1), a new flavonoid glycoside, along with eight known ones (2-9) were isolated from the flowers of Vicia faba L. (Leguminosae) which were identified as kaempferol 3-O-α-arabinopyranosyl-5-O-α-rhamnopyranoside (2), kaempferol 7-O-α-rhamnopyranoside (3), kaempferol 3-O-α-arabinopyranosyl- 7-O-α-rhamnopyranoside (4), kaempferol 3-O-rutinoside (5), kaempferol 3-O-α-rhamnopyranosyl-(1→3)-β-galactopyranosyl-7-O-α-rhamnopyranoside (6), kaempferol-3-O-β-galactopyranosyl-7-O-α-rhamnopyranoside (7), kaempferol-3-O-α-rhamnopyranosyl(1→6)-β-galactopyranosyl-7-O-α- rhamnopyranoside (8) in addition to a quercetin derivative; quercitin-3´-O-α- rhamnopyranosyl-4´-(3´´-acetyl)-β-galactopyranoside (9). Structure elucidation of the new compound was established based on 1D and 2D NMR analyses including 1H-, 13C-NMR, and HMBC experiments, in addition to HR-TOF-MS spectrometry using matrix assisted laser desorption ionization (MALDI).