title: 9, 10-Dihydrophenanthrene derivatives from Pholidota yunnanensis and scavenging activity on DPPH free radical.
abstract: Three new 9,10-dihydrophenanthrene derivatives named phoyunnanins A-C, together with six known 9,10-dihydrophenanthrene constituents, 4,4',7,7'-tetrahydroxy-2,2'-dimethoxy-9,9',10,10'-tetrahydro-1,1'-biphenanthrene (4), lusianthridin (5), eulophiol (6), 2,4,7-trihydroxy-9,10-dihydrophenanthrene (7) and imbricatin (8), were isolated from the 60% ethanolic extract of air-dried whole plant of Pholidota yunnanensis Rolfe. The structures of phoyunnanins A-C were established as 6-[2'-(3',3''-dihydroxy-5'-methoxybibenzy)]-4,7-dihydroxy-2-methoxy-9,10-dihydrophenanthrene (1), 6-[6'-(trans-3',3''-dihydroxy-5'-methoxystilbeny)]-4,7-dihydroxy-2-methoxy-9,10-dihydrophenanthrene (2) and 4,4',7,7'-tetrahydroxy-2,2'-dimethoxy-9,9',10,10'-tetrahydro-1,6'-biphenanthrene (3), respectively, on the basis of the spectroscopic analysis. All eight compounds (1-8) were found to show the DPPH free radical scavenging activity with EC(50) from 8.8 to 55.9 microM.
authors: College of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University. Shenyang, 110016. China.
authors: X-Y
authors: XY
authors: Guo
authors: J
authors: J
authors: Wang
authors: N-L
authors: NL
authors: Wang
authors: S
authors: S
authors: Kitanaka
authors: X-S
authors: XS
authors: Yao
mesh_terms: D016166:Free Radical Scavengers / Q000302:isolation & purification*; D015394:Molecular Structure; D029595:Orchidaceae / Q000737:chemistry*; D010616:Phenanthrenes / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D016166:Free Radical Scavengers; D010616:Phenanthrenes