title: Antifungal and antibacterial naphthoquinones from Newbouldia laevis roots.
abstract: From a dichloromethane extract of Newbouldia laevis roots, four new (6-hydroxydehydroiso-alpha-lapachone, 7-hydroxydehydroiso-alpha-lapachone, 5,7-dihydroxydehydroiso-alpha-lapachone and 3-hydroxy-5-methoxydehydroiso-alpha-lapachone) and six known naphthoquinones have been isolated. Their structures were established by spectroscopic methods (UV, EI mass spectrometry, 1H and 13C NMR) and that of 7-hydroxydehydroiso-alpha-lapachone was confirmed by X-ray crystallography. All naphthoquinones showed antifungal activity against Cladosporium cucumerinum and Candida albicans, and activity against the bacteria Bacillus subtilis and Escherichia coli.
authors.affiliation: Institut de Pharmacognosie et Phytochimie, Université de Lausanne, Switzerland.
authors.forename: S
authors.initials: S
authors.lastname: Gafner
authors.forename: J L
authors.initials: JL
authors.lastname: Wolfender
authors.forename: M
authors.initials: M
authors.lastname: Nianga
authors.forename: H
authors.initials: H
authors.lastname: Stoeckli-Evans
authors.forename: K
authors.initials: K
authors.lastname: Hostettmann
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification*; D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification*; D018360:Crystallography, X-Ray; D009285:Naphthoquinones / Q000737:chemistry / Q000302:isolation & purification*; D010946:Plants, Medicinal / Q000737:chemistry*; D013057:Spectrum Analysis
chemical_list: D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D009285:Naphthoquinones