RESUMO
Highly oxygenated ecdysteroids, (24R)-11 alpha, 20,24-trihydroxyecdysone and 11 alpha,20,26-trihydroxyecdysone, have been isolated from the polar fraction of Vitex canescens root bark. The latter exists as two C-25 epimers which could be separated by reversed-phase HPLC.
Assuntos
Plantas Medicinais , Esteroides/isolamento & purificação , Vitex/química , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Ecdisteroides , Espectroscopia de Ressonância Magnética , Raízes de Plantas/química , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Estereoisomerismo , Esteroides/químicaRESUMO
Activity guided fractionation of extracts from Clausena harmandiana have led to the identification of four known compounds, heptaphylline (1), clausine K (2), dentatin (5), and clausarin (6). All these compounds, except clausine K (2), exhibited antiplasmodial activity against Plasmodium falciparum. While the new dimethylated derivative 4, derived from 2, showed no antiplasmodial activity, the monomethylated product 3 (clausine H) exhibited activity comparable to that observed for compounds 1 and 5.
