title: Two novel dicarboxylic Acid derivatives and a new dimeric hydrolyzable tannin from walnuts.
abstract: In addition to the 16 previously reported polyphenols including 3 new ellagitannins, 2 novel dicarboxylic acid derivatives, glansreginins A (1) and B (2), and a new dimeric hydrolyzable tannin, glansrin D (3), were isolated, together with 15 known compounds from walnuts, the seeds of Juglans regia. The structures of the new compounds were elucidated on the basis of 1D- and 2D-NMR analyses and chemical data. The antioxidant effect of these isolates was also evaluated by SOD-like and DPPH radical scavenging activities.
authors.affiliation: Department of Pharmacognosy, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Tsushima, Okayama 700-8530, Japan. hito@cc.okayama-u.ac.jp
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Ito
authors.forename: Takahiro
authors.initials: T
authors.lastname: Okuda
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Fukuda
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Hatano
authors.forename: Takashi
authors.initials: T
authors.lastname: Yoshida
mesh_terms: D000975:Antioxidants / Q000494:pharmacology; D003998:Dicarboxylic Acids / Q000032:analysis*; D019281:Dimerization; D005419:Flavonoids / Q000032:analysis; D006868:Hydrolysis; D047348:Hydrolyzable Tannins / Q000032:analysis / Q000737:chemistry / Q000494:pharmacology; D031324:Juglans / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D010636:Phenols / Q000032:analysis; D059808:Polyphenols; D012639:Seeds / Q000737:chemistry; D013634:Tannins / Q000032:analysis* / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D003998:Dicarboxylic Acids; D005419:Flavonoids; D047348:Hydrolyzable Tannins; D010636:Phenols; D059808:Polyphenols; D013634:Tannins; C519268:glansrin D