Cytotoxic tetraoxygenated xanthones from the bark of Garcinia schomburgkiana

• Published in: Phytochemistry letters Vol. 5; no. 3; pp. 553 - 557
• Main Authors: Vo, Hau T., Nguyen, Ngoc-Tuyet T., Nguyen, Hieu T., Do, Khoa Q., Connolly, Joseph D., Maas, Gerhard, Heilmann, Jörg, Werz, Udo R., Pham, Hung D., Nguyen, Lien-Hoa D.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-09-2012
• Subjects: 6-O-Demethyloliverixanthone; anticarcinogenic activity; bark; Cytotoxicity; Garcinia; Garcinia schomburgkiana; Guttiferae; inhibitory concentration 50; nuclear magnetic resonance spectroscopy; Schomburgxanthone; Xanthones; Garcinia schomburgkiana; Cytotoxicity; Schomburgxanthone; Xanthones; 6-O-Demethyloliverixanthone; Guttiferae
• ISSN: 1874-3900; 1876-7486
• DOI: 10.1016/j.phytol.2012.05.012

Two new tetraoxygenated xanthones, 6-O-demethyloliverixanthone and schomburgxanthone, together with six known xanthones, were isolated from the bark of Garcinia schomburgkiana. Their structures were elucidated using 1-D and 2-D NMR techniques as well as chemical methods. Five of the isolated compounds were tested for their cytotoxicity against HeLa cells and the result showed that fuscaxanthone B and cowanin possessed remarkable activity with IC50 values of 2.4±0.2 and 2.7±0.3μg/ml, respectively, using an MTT assay. [Display omitted]
► Chemical constituents of the bark of Garcinia schomburgkiana. ► Isolation and structure elucidation of eight compounds. ► Two new tetraoxygenated xanthones, 6-O-demethyloliverixanthone and schomburgxanthone. ► Cytotoxicity against HeLa cells using an MTT assay. ► Fuscaxanthone B and cowanin possessed remarkable activity (IC50 2.4–2.7μg/ml).
Two new tetraoxygenated xanthones, 6-O-demethyloliverixanthone and schomburgxanthone, together with cowanin, cowanol, fuscaxanthones A and B, 3-isomangostin hydrate, and 1,7-dihydroxyxanthone, were isolated from the bark of Garcinia schomburgkiana. Their structures were elucidated using 1-D and 2-D NMR techniques as well as chemical methods. Five of the isolated compounds were tested regarding their cytotoxicity against HeLa cells and the results showed that fuscaxanthone B and cowanin possessed remarkable activity with IC50 values of 2.4±0.2 and 2.7±0.3μg/ml, respectively, using an MTT assay.