New depsidones and xanthone from the roots of Garcinia schomburgkiana.

Two new depsidones, schomburgdepsidones A and B (1 and 2), and one new xanthone, schomburgxanthone A (3), together with eight known compounds (4-11) were isolated from the roots of Garcinia schomburgkiana. Their chemical structures were established on the basis of spectroscopic analysis. The in vitro cytotoxicity of all 11 compounds was evaluated against the KB, HeLa S-3, HT-29, MCF-7 and Hep G2 human cancer cell lines. Compound 7 performed a good cytotoxicity against the KB, Hela S-3 and MCF-7 cell lines with IC50 values in the range of 3.17-6.07μM. Compound 3 exhibited a good cytotoxicity against the KB cell line only, with an IC50 value of 8.14μM.