A new bisanthraquinone and cytotoxic xanthones from Cratoxylum cochinchinense.

A new bisanthraquinone has been isolated from the stems of Cratoxylum cochinchinense together with vismiaquinone C and 16 known xanthones. Their structures were characterised by using spectroscopic methods. Two of the isolated compounds are modified xanthones (6 and 15) and exhibited strong cytotoxicity against human epidermoid carcinoma (A341: IC50 2.01, 1.78 mu g/mL) and human breast cancer cell lines (SKBR3: IC50 1.54, 0.69 mu g/mL).