title: Flavan and procyanidin glycosides from the bark of blackjack oak.
abstract: The bark of blackjack oak contains (+)-catechin, (-)-epicatechin, (+)-3-O-[beta-D-glucopyranosyl]-catechin, catechin-(4 alpha-->8)-catechin, epicatechin-(4 beta-->8)-catechin as well as the novel 3-O-[beta-D-glucopyranosyl]-catechin-(4 alpha-->8)-catechin and 3-O-[alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranosyl]-catechin, as major components. The latter rutinoside of catechin is especially interesting because of the exceptionally small J2,3 C-ring coupling. The glucoside of catechin-(4 alpha-->8)-catechin is only the second proanthocyanidin found in nature in which a 3-O-glycoside is present in the upper 'extender unit' of a dimer.
authors.affiliation: Southern Forest Experiment Station, USDA Forest Service, Pineville, LA 71360.
authors.forename: Y S
authors.initials: YS
authors.lastname: Bae
authors.forename: J F
authors.initials: JF
authors.lastname: Burger
authors.forename: J P
authors.initials: JP
authors.lastname: Steynberg
authors.forename: D
authors.initials: D
authors.lastname: Ferreira
authors.forename: R W
authors.initials: RW
authors.lastname: Hemingway
mesh_terms: D044946:Biflavonoids; D002240:Carbohydrate Sequence; D002392:Catechin / Q000737:chemistry / Q000302:isolation & purification*; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification*; D006027:Glycosides / Q000737:chemistry / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D015394:Molecular Structure; D044945:Proanthocyanidins; D014197:Trees / Q000737:chemistry*
chemical_list: D044946:Biflavonoids; D005419:Flavonoids; D006027:Glycosides; D044945:Proanthocyanidins; C017674:procyanidin; D002392:Catechin