Cytotoxic constituents of the twigs of Simarouba glauca collected from a plot in Southern Florida.

Activity-guided fractionation of a chloroform-soluble extract of Simarouba glauca twigs collected from a plot in southern Florida, and monitored with a human epidermoid (KB) tumor cell line, afforded six canthin-6-one type alkaloid derivatives, canthin-6-one (1), 2-methoxycanthin-6-one (2), 9-methoxycanthin-6-one (3), 2-hydroxycanthin-6-one (4), 4,5-dimethoxycanthin-6-one (5) and 4,5-dihydroxycanthin-6-one (6), a limonoid, melianodiol (7), an acyclic squalene-type triterpenoid, 14-deacetyleurylene (8), two coumarins, scopoletin (9) and fraxidin (10), and two triglycerides, triolein (11) and trilinolein (12). Among these isolates, compounds 1-4, 7 and 8 exhibited cytotoxic activity against several human cancer cell lines. 14-Deacetyleurylene (8) was selectively active against the Lu1 human lung cancer cell line, but was inactive in an in vivo hollow fiber assay using this same cell type. Copyright 2005 John Wiley & Sons, Ltd.