The activity of hydroxynaphthoquinones against Leishmania donovani.

The hydroxynaphthoquinones, buparvaquone, 250C80 and 56W82, showed high activity in vitro against Leishmania donovani amastigotes in mouse peritoneal macrophages, with ED50 values of 0.05, 2.95 and 13.82 microM, respectively. Fourteen other hydroxynaphthoquinones were tested, of which only 566C80 and 608C86 showed significant activity against amastigotes. Buparvaquone, 250C80 and 56W82 were also highly-active against cultured promastigotes. In a BALB/c mouse model, treatment with 100 mg/kg/day for five days with buparvaquone, 250C80 and 566C80 (atovaquone) reduced liver amastigote numbers by 60%, 22% and 30.5%, respectively.