Isoxazolylnaphthoquinone effects on the growth of Trypanosoma cruzi.

Knowing the need for new drugs against the etiologic agent of Chagas disease and considering the biological properties of naphthoquinones and isoxazoles, the effect of three isoxazolyl-naphthoquinones on the growth of Trypanosoma cruzi was studied. To evaluate the activity of the compounds on epimastigote forms, growth curves with different concentrations of 2-hydroxi-N-(3,4-dimethyl-5-isoxazolyl)-1,4-naphthoquinone-4 -imine (I), N-(3,4-dimethyl-5-isoxazolyl)-4-amino-1,2-naphthoquinone (II), 2-acetyl-N-(3,4-dimethyl-5-isoxazolyl)-1,4-naphthoquinone-imine (III) and Nifurtimox as reference drug were made. The studies on the trypomastigote form were performed on two month old BALB/c mice, evaluating parasitemia on day 13 post infection. The results obtained with epimastigotes showed that all drugs induced alterations in motility, morphology, viability and/or lysis of parasites. For the treatments on trypomastigotes the best results were obtained with (I) which reduced parasitemia compared to untreated controls.