title: Constituents from leaves of Apocynum venetum L.
abstract: An analysis using HPLC-MS revealed that an extract from dried leaves of Apocynum venetum L. contained more than 15 kinds of phenolic constituents. Two malonated flavonol glycosides were further isolated, and their structures were determined to be quercetin 3-O-(6''-O-malonyl)-beta-D-glucoside (1) and quercetin 3-O-(6''-O-malonyl)-beta-D-galactoside (2) by NMR spectroscopic analysis. This is the first report describing the isolation of these malonated flavonol glycosides from A. venetum L. Both glycosides showed strong scavenging activity against 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical.
authors.affiliation: Tokiwa Phytochemical Co., Ltd., 158 Kinoko, Sakura, Chiba, 285-0801, Japan.
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Kamata
authors.forename: Shujiro
authors.initials: S
authors.lastname: Seo
authors.forename: Jun-ichiro
authors.initials: J
authors.lastname: Nakajima
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification; D030010:Apocynum / Q000737:chemistry*; D001713:Biphenyl Compounds; D002851:Chromatography, High Pressure Liquid; D016166:Free Radical Scavengers / Q000737:chemistry / Q000302:isolation & purification*; D005697:Galactosides / Q000737:chemistry / Q000302:isolation & purification*; D005960:Glucosides / Q000737:chemistry / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D010636:Phenols / Q000737:chemistry* / Q000302:isolation & purification; D010851:Picrates / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification; D018515:Plant Leaves / Q000737:chemistry*; D011794:Quercetin / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D005697:Galactosides; D005960:Glucosides; D010636:Phenols; D010851:Picrates; D010936:Plant Extracts; C529809:quercetin 3-O-(6''-O-malonyl)galactoside; C529808:quercetin 3-O-(6''-O-malonyl)glucoside; D011794:Quercetin; C004931:1,1-diphenyl-2-picrylhydrazyl