title: Phenolic constituents from Rhopalocnemis phalloides with DPPH radical scavenging activity.
abstract: The 80% aqueous acetone extract of the whole plant of Rhopalocnemis phalloides Jungh. (Balanophoraceae) showed obvious radical scavenging activity (SC(50) = 32.1 mug/mL) on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical assay. Further chemical investigation of the extract led to the isolation of 12 phenolic compounds (1-12). Among these, bis-6,8'-catechinylmethane (2), a flavan-3-ol dimer, was first isolated as a natural product from Rhopalocnemis phalloides. The full NMR assignments of bis-catechinylmethanes (1 and 2) are reported for the first time, on the basis of detailed spectroscopic analysis. The DPPH assay showed that flavan-3-ol dimers (1-3) had remarkable free radical scavenging activity, while flavonoid aglycones (4 and 9) presented stronger activities than those of their glycosides (5-8 and 10).
authors.affiliation: State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, People's Republic of China.
authors.forename: Gai-Mei
authors.initials: GM
authors.lastname: She
authors.forename: Jin-Bo
authors.initials: JB
authors.lastname: Hu
authors.forename: Ying-Jun
authors.initials: YJ
authors.lastname: Zhang
authors.forename: Chong-Ren
authors.initials: CR
authors.lastname: Yang
mesh_terms: D031111:Balanophoraceae; D001713:Biphenyl Compounds / Q000302:isolation & purification* / Q000494:pharmacology; D016166:Free Radical Scavengers / Q000302:isolation & purification* / Q000494:pharmacology; D010636:Phenols / Q000302:isolation & purification* / Q000494:pharmacology; D010851:Picrates / Q000302:isolation & purification* / Q000494:pharmacology; D010936:Plant Extracts / Q000302:isolation & purification* / Q000494:pharmacology
chemical_list: D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D010636:Phenols; D010851:Picrates; D010936:Plant Extracts; C004931:1,1-diphenyl-2-picrylhydrazyl