title: Regioselectivity in benzotropolone formation between catechins and proanthocyanidins.
abstract: A theaflavin-related benzotropolone pigment formed between procyanidin B-1 and (-)-epigallocatechin was synthesized enzymatically for the first time. The condensation occurred regioselectively at the extension (upper) unit of the procyanidin, probably due to a steric effect.
authors.affiliation: Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Tanaka
authors.forename: Kyoko
authors.initials: K
authors.lastname: Inoue
authors.forename: Isao
authors.initials: I
authors.lastname: Kouno
mesh_terms: D044946:Biflavonoids / Q000138:chemical synthesis*; D002392:Catechin / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D044945:Proanthocyanidins / Q000138:chemical synthesis / Q000737:chemistry*; D027843:Vitis
chemical_list: D044946:Biflavonoids; D044945:Proanthocyanidins; C508389:benzotropolone; D002392:Catechin