title: Cytotoxic Flavonoid Glycosides from Rapistrum rugosum L.
abstract: Five flavonoid glycosides were isolated from the n-butanol soluble fraction of the ethanolic extract of Rapistrum rugosum and their structures were assigned from (1)H- and (13)C-NMR spectra (DEPT) with 2D NMR as quercetin-3-O-α-L-rhamnopyranoside (1), quercetin-3-O- β-D-xyloside (2), quercetin, 3-O-α-L-arabinopyranoside,7-O-α-L-rhamnopyranoside (3), kaempferol 3-O-α-L-arabinopyranoside, 7-O-α-L-rhamnopyranoside (4) and rutin (5). The SRB cytotoxic assay was used to investigate the antitumor activities of n-butanol extract, compound 3 and its hexaacetate 3a, for the first time. Compounds 3 and 3a showed cytotoxic activity against the human cancer cell line, namely, HepG2 (hepatocellular carcinoma cell line) with IC50 (concentration of compound required to reduce cell survival by 50%) 0.86 μg/mL and 3.50 μg/mL, respectively. These results proved that compound 3, the major flavonoid of the n-butanol soluble fraction, has significant cytotoxic activity compared with the standard antitumor drug doxorubicin (0.60 μg/mL).
authors.affiliation: Department of Pharmacognosy, College of Pharmacy, King Saud University, Riyadh, Kingdom of Saudi Arabia.
authors.forename: Areej
authors.initials: A
authors.lastname: Mohamed Al-Taweel
authors.forename: Ghada
authors.initials: G
authors.lastname: Ahmed Fawzy
authors.forename: Shagufta
authors.initials: S
authors.lastname: Perveen
keywords: Flavonoid glycosides; Rapistrum rugosum; SRB cytotoxic assay; n-butanol