title: Cytotoxic xanthones from Garcinia penangiana Pierre.
abstract: Two new xanthones, characterized as 4-(1,1-dimethylprop-2-enyl)-1,3,5,8-tetrahydroxyxanthone (1) and penangianaxanthone (2), with three known xanthones, cudratricusxanthone H (3), macluraxanthone C (4) and gerontoxanthone C (5), as well as friedelin and stigmasterol were isolated from the leaves of Garcinia penangiana. Their structures were elucidated by analysis of spectroscopic data and comparison of the NMR data with the literature ones. Significant cytotoxicity against DU-145, MCF-7 and NCI-H460 cancer cell lines was demonstrated by compounds 1-5, with IC50 values ranging from 3.5 to 72.8 microM.
authors.affiliation: Laboratory of Natural Products, Institute of Bioscience, University Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
authors.forename: Md Lip
authors.initials: ML
authors.lastname: Jabit
authors.forename: Rozida
authors.initials: R
authors.lastname: Khalid
authors.forename: Faridah
authors.initials: F
authors.lastname: Abas
authors.forename: Khozirah
authors.initials: K
authors.lastname: Shaari
authors.forename: Lim Siang
authors.initials: LS
authors.lastname: Hui
authors.forename: Johnson
authors.initials: J
authors.lastname: Stanslas
authors.forename: Nordin H
authors.initials: NH
authors.lastname: Lajis
mesh_terms: D029760:Garcinia / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008296:Malaysia; D044004:Xanthones / Q000032:analysis* / Q000737:chemistry / Q000633:toxicity*
chemical_list: D044004:Xanthones