title: Dibenzofuran and pyranone metabolites from Hypericum revolutum ssp. revolutum and Hypericum choisianum.
abstract: In a project to isolate and characterise anti-staphylococcal compounds from members of the genus Hypericum, a dibenzofuran and a pyranone were isolated from the dichloromethane and hexane extracts of Hypericum revolutum ssp. revolutum Vahl (Guttiferae) and Hypericum choisianum Wall. ex. N. Robson (Guttiferae), respectively. The structures of these compounds were elucidated by 1- and 2D-NMR spectroscopy and mass spectrometry as 3-hydroxy-1,4,7-trimethoxydibenzofuran (1) and 4-(3-O-3'')-3''-methylbutenyl-6-phenyl-pyran-2-one (2). The metabolites were evaluated against a panel of multidrug-resistant strains of Staphylococcus aureus. Compound 1 exhibited a minimum inhibitory concentration (MIC) of 256 microg/ml, whereas compound 2 was inactive at a concentration of 512 microg/ml.
authors.affiliation: Centre for Pharmacognosy and Phytotherapy, The School of Pharmacy, University of London, 29-39 Brunswick Square, London WC1N 1AX, UK.
authors.forename: Winnie Ka Po
authors.initials: WK
authors.lastname: Shiu
authors.forename: Simon
authors.initials: S
authors.lastname: Gibbons
mesh_terms: D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D001572:Benzofurans / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D020902:Hypericum / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D011753:Pyrones / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000935:Antifungal Agents; D001572:Benzofurans; D011753:Pyrones; C023614:dibenzofuran