Antimalarial activity of neurolenin B and derivates of Eupatorium inulaefolium (Asteraceae).

Dried stems and leaves of Eupatorium inulaefolium (Austroeupatorium inulaefolium) (Asteraceae) were used to obtain four crude extracts (hexane, dichloromethane, methanol and ethanol). Two fractions were obtained from the hexane extract (S1 and S2) and three compounds (neurolenin B, lobatin A and lobatin B) from the dichloromethane extract. The ethanol, hexane, dichloromethane and methanol extracts, two fractions from the hexane extract (S1 and S2), and neurolenin B were evaluated in vitro against Plasmodium falciparum, FCB-2 strain. Two extracts (dichloromethane and methanol), the S2 fraction and neurolenin B showed statistically significant antiplasmodial activity.