Four naphthoquinones were submitted to the action of diazomethane. The stru
cture of the nine adducts, of which four were original, was determined. The
protozoocidal activity of these compounds was evaluated in vitro against P
lasmodium falciparum, Leishmania donovani, Trypanosoma brucei and Trichomon
as vaginalis. The 2-methoxy-naphthoquinone <(3a)under bar> exhibited some a
ctivity and was more potent against these four protozoa than the reference
drugs. The 2-methoxynaphthoquinone <(4a)under bar> showed more activity tha
n chloroquine towards Plasmodium falciparum.