title: Prenylflavonol, acylated flavonol glycosides and related compounds from Epimedium sagittatum.
abstract: Chemical examination of the n-BuOH extract from the aerial parts of Epimedium sagittatum led to isolation of three prenylated flavonol glycosides sagittasine A-C, two acylated flavonol glycosides kaempferol-3-O-(2''-E-p-coumaroyl,4''-Z-p-coumaroyl)-alpha-l-rhamnopyranoside and kaempferol-3-O-(3''-Z-p-coumaroyl,4''-E-p-coumaroyl)-alpha-l-rhamnopyranoside, together with known flavonoids, flavonolignans, 2-phenoxychromones, a lignan, and aromatic acid derivatives. Flavonolignans were identified for the first time in this plant. The vasorelaxing properties of the n-BuOH extract of E. sagittatum and 13 isolated compounds were tested using pre-contracted rat aorta rings in an organ bath apparatus. The results indicated that the n-BuOH extract of E. sagittatum produced a partial endothelial nitric oxide-dependent vasorelaxation, with EC(50) of 0.16+/-0.03 mg/ml. However, the 13 compounds tested, generated only a mild or moderate relaxation, and did not possess significant vasorelaxing effect individually.
authors.affiliation: National Research Institute of Chinese Medicine, 155-1, Li-Nong Street Section 2, Taipei 112, Taiwan.
authors.forename: Guei-Jane
authors.initials: GJ
authors.lastname: Wang
authors.forename: Tung-Hu
authors.initials: TH
authors.lastname: Tsai
authors.forename: Lie-Chwen
authors.initials: LC
authors.lastname: Lin
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D034181:Epimedium / Q000737:chemistry*; D044948:Flavonols / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D006027:Glycosides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D066298:In Vitro Techniques; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013056:Spectrophotometry, Ultraviolet; D014664:Vasodilation / Q000187:drug effects
chemical_list: D044948:Flavonols; D006027:Glycosides