title: Unusual phenolic glycosides from Cotoneaster orbicularis.
abstract: The whole plant of Cotoneaster orbicularis contains the novel di-C-glycosylflavone, 4",4"'-di-O-beta-glucopyranosyl-vicenin II, or 6,8-di-C-beta-Cellobiosylapigenin, as well as the hitherto unknown natural phenolic glucoside, gentisic acid 2-O-beta-glucopyranoside, or orbicularin. Further phenolics are protocatechuic, anisic, caffeic, p-coumaric acids, catechin, epicatechin, 2"-O-alpha-rhamnopyranosylvitexin, vitexin, rutin, isoquercetrin, hyperin and naringenin. All structures were determined by routine methods of analysis and confirmed mostly by 1H- and 13C-NMR.
authors.affiliation: National Research Centre, El-Dokki, Cairo, Egypt.
authors.forename: A M
authors.initials: AM
authors.lastname: El-Mousallamy
authors.forename: S A
authors.initials: SA
authors.lastname: Hussein
authors.forename: I
authors.initials: I
authors.lastname: Merfort
authors.forename: M A
authors.initials: MA
authors.lastname: Nawwar
mesh_terms: D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification*; D005841:Gentisates; D005960:Glucosides / Q000737:chemistry / Q000302:isolation & purification*; D006027:Glycosides / Q000737:chemistry / Q000302:isolation & purification*; D062385:Hydroxybenzoates / Q000737:chemistry / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy; D010636:Phenols / Q000737:chemistry / Q000302:isolation & purification*; D010936:Plant Extracts / Q000737:chemistry; D019685:Rosales / Q000737:chemistry*
chemical_list: C411340:6,8-di-C-cellobiosylapigenin; D005419:Flavonoids; D005841:Gentisates; D005960:Glucosides; D006027:Glycosides; D062385:Hydroxybenzoates; D010636:Phenols; D010936:Plant Extracts; C411341:orbicularin