title: Rare biscoumarins and a chlorogenic acid derivative from Erycibe obtusifolia.
abstract: Three coumarins, 7,7'-dihydroxy-6,6'-dimethoxy-3,3'-biscoumarin (1), 7,7'-dihydroxy-6,6'-dimethoxy-8,8'-biscoumarin (2) and 7-O-[4'-O-(3'',4''-dihydroxycinnamyl)-beta-d-glucopyranosyl]-6-methoxycoumarin (3), and a chlorogenic acid derivative, methyl-3-O-(4''-hydroxy-3'',5''-dimethoxybenzoyl)-chlorogenate (4) were isolated from the roots of Erycibe obtusifolia along with four known coumarins, scopoletin (5), scopolin (6), cleomiscosin A (7) and cleomiscosin B (8). Their structures were elucidated by spectroscopic methods. Among them, compounds (1) and (2) are rare carbon-carbon linked symmetrical biscoumarins.
authors.affiliation: Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine (Ministry of Education), Institute of Materia Medica, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100050, PR China.
authors.forename: Jian
authors.initials: J
authors.lastname: Liu
authors.forename: Ziming
authors.initials: Z
authors.lastname: Feng
authors.forename: Jianfu
authors.initials: J
authors.lastname: Xu
authors.forename: Yinghong
authors.initials: Y
authors.lastname: Wang
authors.forename: Peicheng
authors.initials: P
authors.lastname: Zhang
mesh_terms: D002726:Chlorogenic Acid / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification; D027722:Convolvulaceae / Q000737:chemistry*; D003374:Coumarins / Q000737:chemistry* / Q000302:isolation & purification; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular
chemical_list: D003374:Coumarins; C523836:methyl-3-O-(4'-hydroxy-3',5'-dimethoxybenzoyl)chlorogenate; D002726:Chlorogenic Acid