RESUMO
Five prenylated flavonoids, 8-(1,1-dimethylallyl)genistein (1), 5,7,3',4'-tetrahydroxy-2',5'-di(3-methylbut-2-enyl)isoflavone (2), 5,7,3'-trihydroxy-2'-(3-methylbut-2-enyl)-4',5'-(3,3-dimethylpyrano)isoflavone (3), (2R)-5,2',4'-trihydroxy-8,5'-di(3-methylbut-2-enyl)-6,7-(3,3-dimethylpyrano)flavanone (4a) and (2S)-5, 2', 4'-trihydroxy-8,5'-di(3-methylbut-2-enyl)-6,7-(3,3-dimethylpyrano)flavanone (4b), were isolated from the roots of Moghania philippinensis. The structures of these compounds were determined on the basis of spectroscopic and chemical means.
Assuntos
Fabaceae/química , Flavonoides/química , Terpenos/química , Flavonoides/isolamento & purificação , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química , Plantas Medicinais/química , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Ultravioleta , EstereoisomerismoRESUMO
For the purpose of developing novel anti-hepatitis C virus (HCV) agents from natural resources, 93 Yunnan crude drugs were screened for their inhibitory effects on RNA-dependent RNA polymerase (RdRp) of HCV. Although 71 methanol extracts and 50 water extracts inhibited HCV-RdRp by more than 50% at a concentration of 50 µg/ml, the majority of them contained a high percentage of tannins. However, methanol extracts of Plumbago zeylanica (branch), Maytenus fookerii (leaf) and Huashidancha (Y61, branch and leaf), and water extracts of Potentilla griffithii (whole plant) and Salvia yunnanensis (underground part), having IC50 values of less than 10 µg/ml, showed less than 10% tannin content. In addition, from a methanol extract of Tripterygium hypoglaucum (root bark), demethylzeylasteral was isolated as a strongly inhibitory substance against HCV-RdRp.