title: A new chromanone acid from the stem bark of Calophyllum teysmannii.
abstract: A new chromanone acid, namely caloteysmannic acid (1), along with three known compounds, calolongic acid (2), isocalolongic acid (3) and stigmasterol (4) were isolated from the stem bark of Calophyllum teysmannii. All these compounds were evaluated for their cytotoxic and antioxidant activities in the MTT and DPPH assays, respectively. The structure of compound 1 was determined by means of spectroscopic methods including 1D and 2D NMR experiments as well as HR-EIMS spectrometry. The stereochemical assignment of compound 1 was done based on the NMR results and X-ray crystallographic analysis. The preliminary assay results revealed that all the test compounds displayed potent inhibitory activity against HeLa cancer cell line, in particular with compound 1 which exhibited the highest cytotoxic activity comparable to the positive control used, cisplatin. However, no significant antioxidant activity was observed for all the test compounds in the DPPH radical scavenging capacity assay.
authors.affiliation: a Faculty of Science, Universiti Tunku Abdul Rahman, Jalan Universiti , Bandar Barat, 31900 Kampar , Perak , Malaysia.
authors.forename: Chan Kiang
authors.initials: CK
authors.lastname: Lim
authors.forename: Hemaroopini
authors.initials: H
authors.lastname: Subramaniam
authors.forename: Yee How
authors.initials: YH
authors.lastname: Say
authors.forename: Vivien Yi Mian
authors.initials: VY
authors.lastname: Jong
authors.forename: Hamid
authors.initials: H
authors.lastname: Khaledi
authors.forename: Chin Fei
authors.initials: CF
authors.lastname: Chee
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry* / Q000302:isolation & purification; D029759:Calophyllum / Q000737:chemistry*; D002867:Chromones / Q000737:chemistry* / Q000302:isolation & purification; D016166:Free Radical Scavengers / Q000737:chemistry / Q000302:isolation & purification; D006367:HeLa Cells; D006801:Humans; D015394:Molecular Structure; D024301:Plant Bark / Q000737:chemistry*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D002867:Chromones; D016166:Free Radical Scavengers; C000603256:caloteysmannic acid
keywords: Calophyllum teysmannii; NMR spectroscopy; X-ray crystallography; caloteysmannic acid; chromanone acid; cytotoxic