New Flavonol Glycoside from the Leaves of Ventilago africana.

A new flavonol diglycoside, rhamnocitrin-3-O-α-L-rhamnopyranosyl-(1-->6)-β-D-galactopyranoside, was isolated from the leaves of Ventilago Africana, in addition to 11 known flavonoids. Their structures were determined by spectroscopic methods including 1D- and 2D-NMR, and HR-ESI-MS analysis. The isolated compounds were evaluated for their antioxidant activity by using DPPH radical-scavenging assay. Compounds 4, 7-9 have discrete to good antioxidant potential with EC50 values ranging from 20.9 to 40.4 µM, compared with ascorbic acid (EC50 60 µM) used as positive control.