Chem. Pharm. Bull., 50(7),981-984, July 2002

Notes

New Flavonol Tetraglycosides from Astragalus caprinus

Nabil SEMMAR,^a Bernard FENET,^b Katia GLUCHOFF-FIASSON,^a Gilles COMTE,^c and Maurice JAY^a

^a Laboratoire de Phytochimie et Biologie Micromoleculaire, UFR de Biologie, Université Lyon 1; ^b Centre de RMN, UCBESCPE, UPRESA CNRS 5012, Université Lyon 1; and ^c Laboratoire des Produits Naturels,UMR CNRS 5013, UFR de Chimie-Biochimie, Université Lyon 1; 43 Bd. 11 Novembre, 69622 Villeurbanne, France.

A new flavonol tetraglycoside, together with four acylated derivatives, were isolated from the leaves of Astragalus caprinus. Their structures were elucidated by spectroscopic methods, mainly 2D NMR, as kaempferol-3-O-{[ β-D-xylopyranosyl(13)-α-L-rhamnopyranosyl(16)][ α-L-rhamnopyranosyl(12)]}-β-D-galactopyranoside (1), its 3^Gal-p-coumaric (2) and 3^Gal-ferulic (3) esters, and its 4^Gal-p-coumaric (4) and 4^Gal-ferulic (5) esters.

Key words Astragalus caprinus; Fabaceae; acylated flavonol tetraglycoside; flavonol tetraglycoside; kaempferol