Anti-trypanosomal Activity of Helenalin and Some Structurally Related Sesquiterpene Lactones

Abstract

The anti-trypanosomal activity of six sesquiterpene lactones (helenalin, mexicanin I, 11α,13-dihydrohelenalin acetate, chamissonolide, ivalin and isoalantolactone) against the African Trypanosoma brucei rhodesiense and American T. cruzi was investigated. All tested compounds were found active towards both parasites, the former being generally more sensitive. Helenalin was the most active compound in the series with IC₅₀ values of 0.051 and 0.695 μM against T. brucei rhodesiense and T. cruzi, respectively. The low IC₅₀ value for T. b. rhodesiense indicates that helenalin type compounds may be interesting candidates for further evaluation.

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