Antiplasmodial prenylated flavonoids from stem bark of Erythrina latissima

The antiplasmodial activity against Plasmodium falciparum strain K1 as well as Erythrina latissima E. Mey (Leguminosae) from South Africa was determined. Although initially some promising activities were observed, with 5'-prenyl-pratensein being the most selective compound, most IC50 values varied from 1 to 30 mu M, with cytotoxicities in the same range, resulting in selectivity indices < 10. The prenylated flavonoid scaffold can be considered as a promising skeleton for antiplasmodial compounds, but structural modifications to reduce the cytotoxiciy and to improve the selectivity will be necessary.