Antiplasmodial activity of isolated compounds from Carpesium divaricatum.

The whole plants of Carpesium divaricatum are used in traditional medicine as an antipyretic, analgesic and vermifugic, including a topical application for sores and inflammation. In a previous paper, the isolation and structural elucidation of isolated ineupatorolides A from methanol extracts of C. rosulatum (Compositae) were reported. The present paper deals with the isolation and identification of antiplasmodial compounds from C. divaricatum in Carpesium spp. Five compounds, 1 beta,6 alpha-dihydroxy-4(15)-eudesmene [1], beta-dictyopterol [2], 2-isopropenyl-6-acetyl-8-methoxy-1,3-benzodioxin-4-one [3], (3E,6E,10E,14E,18E)-2,6,10,15,19,23-hexamethyl-3,6,10,14,18,22-tetracosahexaen-2-ol [4] and neophytadiene [5], were isolated from the whole plants of C. divaricatum. The in vitro activity against P. falciparum strain D10 was assessed using the parasite lactate dehydrogenase assay method. The main antiplasmodial principle, 2-isopropenyl-6-acetyl-8-methoxy-1,3-benzodioxin-4-one [3], has been isolated from C. divaricatum for the first time. Compound 3 exhibited an antiplasmodial activity with IC(50) values of 2.3 +/- 0.3 microm. This is the first report on the antiplasmodial activity of the compounds from C. divaricatum.