J Ethnopharmacol. 1998 Jul; 61(3): 179-83.

Bioassay-guided isolation of a diastereoisomer of kolavenol from Entada abyssinica active on Trypanosoma brucei rhodesiense.

Freiburghaus F, Steck A, Pfander H, Brun R.

University of Berne, Department of Chemistry and Biochemistry, Switzerland.

Bioassay-guided fractionation of the dichloromethane rootbark extract of Entada abyssinica (Leguminosae), a plant used by traditional healers in Uganda for the treatment of sleeping sickness, led to the isolation of a diastereoisomer of the clerodane type diterpene kolavenol. This is the first report on this compound. It showed a trypanocidal activity with an IC50 value of 2.5 microg/ml (8.6 microM) against Trypanosoma brucei rhodesiense, the causing agent of the acute form of human African trypanosomiasis.