Cytotoxic compounds of Schizolaena hystrix from the Madagascar rainforest.

Bioassay-guided fractionation of a crude ethanol extract from a Madagascar collection of Schizolaena hystrix afforded the two new long-chain compounds, 3 S-acetoxyeicosanoic acid ethyl ester ( 1) and 3 S-acetoxydoeicosanoic acid ( 2), and the known long-chain compound 3 S-acetoxyeicosanoic acid ( 3). In addition, the long-chain alcohol 1-hydroxydodecan-2-one ( 7), as well as the new flavonoid schizolaenone C ( 4) and the two known flavonoids diplacol ( 5) and 3'-prenylnaringenin ( 6) were isolated from a methanol extract of the same plant. Isolation and structure elucidation of the novel compounds and the cytotoxicities of all the isolates are reported.