Coumaroyl flavonol glycosides from the leaves of Ginkgo biloba.
Two coumaroyl flavonol glycosides, isorhamnetin 3-O-alpha-L-[6"'-p-coumaroyl-(beta-D)-glucopyranosyl-(1,2)-rhamnopyranoside], and kaempferol 3-O-alpha-L-[6"'-p-coumaroyl-(beta-D)-glucopyranosyl-(1,2)-rhamnopyranoside]-7-O-beta-D-glucopyranoside, were isolated from the n-BuOH extract of Ginkgo biloba leaves. These two, together with six other flavonol glycosides, kaempferol 3-O-alpha-L-[6"'-p-coumaroyl-(beta-D)-glucopyranosyl-(1,2)-rhamnopyranoside], quercetin 3-O-alpha-L-[6"'-p-coumaroyl-(beta-D)-glucopyranosyl-(1,2)-rhamnopyranoside], quercetin 3-O-alpha-L-[6"'-p-coumaroyl-(beta-D)-glucopyranosyl-(1,2)-rhamnopyranoside]-7-O-beta-D-glucopyranoside, quercetin 3-O-beta-D-glucopyranosyl-(1-2)-alpha-L-rhamnopyranoside, quercetin 3-O-beta-rutinoside, and quercetin 3-O-beta-D-glucopyranoside, showed profound antioxidant activities in DPPH and cytochrome-c reduction assays using the HL-60 cell culture system.
Tang
Y
Y
Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing 210038, PR China. yptang@pub.sioc.ac.cn
Lou
F
F
Wang
J
J
Li
Y
Y
Zhuang
S
S
D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D005419:Flavonoids / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D044948:Flavonols; D020441:Ginkgo biloba / Q000737:chemistry*; D044949:Kaempferols; D018515:Plant Leaves / Q000737:chemistry; D011794:Quercetin / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology
D000975:Antioxidants; D005419:Flavonoids; D044948:Flavonols; D044949:Kaempferols; C047368:3-methylquercetin; C006552:kaempferol; D011794:Quercetin