Isolation of the New Antiplasmodial Butanolide Malleastrumolide A from a Malleastrum sp. (Meliaceae) from Madagascar.

An extract of Malleastrum sp. (Meliaceae) collected in Madagascar by the Madagascar International Cooperative Biodiversity Group was found to have antimalarial activity, with an IC50 value between 2.5 and 5gml(-1). After purification by liquid-liquid partition, chromatography on a Diaion open column, C18SPE and C-18 reversed phase HPLC, the new butanolide, malleastrumolide A, was isolated. The structure of malleastrumolide A was determined by mass spectrometry, NMR, and ECD. The double bond position was determined by cross-metathesis and mass spectrometry. The compound has antiproliferative activity against the A2780 ovarian cancer cell line with an IC50 value of 17.4m and antiplasmodial activity against the drug-resistant Dd2 strain of Plasmodium falciparum with an IC50 value of 2.74m.