Potential anticancer agents vi. Constituents of Ailanthus excelsa (Simaroubaceae)

Ailanthione (1), glaucarubinone (2) and a mixture of glaucarubol 15-isovalerate (3) and 13,18-dehydroglaucarubol 15-isovalerate (4) were found to be the compounds responsible for the antitumor and cytotoxic activities of extracts of the root bark of Ailanthus excelsa (Simaroubaceae). The latter compound, 4, is new.