title: Xanthones from a microfungus of the genus Xylaria.
abstract: Chemical investigations of a microfungus Xylaria sp. isolated from the Australian rainforest tree Glochidion ferdinandi have afforded two new natural products, 2-hydroxy-6-methyl-8-methoxy-9-oxo-9H-xanthene-1-carboxylic acid (1) and 2-hydroxy-6-hydroxymethyl-8-methoxy-9-oxo-9H-xanthene-1-carboxylic acid (2). Compound 1 has previously been synthesised but only partially characterised. Methylation of 1 using diazomethane afforded the crystalline compound 2,8-dimethoxy-6-methyl-9-oxo-9H-xanthene-1-carboxylic acid methyl ester (3), whose structure was determined by single crystal X-ray analysis. This paper reports the full spectroscopic characterisation of compounds 1-3 by NMR, UV, IR and MS data. All compounds were inactive in a brine shrimp lethality assay and several antimicrobial screens.
authors.affiliation: Chemical Biology Program, Eskitis Institute, Griffith University, Nathan Campus, Brisbane, QLD 4111, Australia.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Healy
authors.forename: Ailsa
authors.initials: A
authors.lastname: Hocking
authors.forename: Nai
authors.initials: N
authors.lastname: Tran-Dinh
authors.forename: John I
authors.initials: JI
authors.lastname: Pitt
authors.forename: Roger G
authors.initials: RG
authors.lastname: Shivas
authors.forename: Jennifer K
authors.initials: JK
authors.lastname: Mitchell
authors.forename: Mike
authors.initials: M
authors.lastname: Kotiw
authors.forename: Rohan A
authors.initials: RA
authors.lastname: Davis
mesh_terms: D001203:Ascomycota / Q000737:chemistry*; D007928:Lethal Dose 50; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008745:Methylation; D008826:Microbial Sensitivity Tests; D008860:Microscopy, Ultraviolet; D015394:Molecular Structure; D010946:Plants, Medicinal / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D014197:Trees / Q000382:microbiology; D044004:Xanthones / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D044004:Xanthones