Neglected diseases are a class of diseases caused mostly by parasites, and they affect more than 1,5 billion people around the world, including 836 million of children. Schistosomiasis and Chagas disease are part of this class, and both present many problems related to pharmacological treatment, especially in relation to resistance and toxicity. Therefore, its necessary to develop new schistosomicidal and antichagasic compounds. In view of this, in 1968, Asato and Berkelhammer synthesized megazol, which is a 5-nitroimidazole derivative that has a high antiparasitic activity. However, this compound also presented mutagenic activity and could not be used for therapy purposes. However, by means of planar molecular modifications, safer and more potent derivatives can be obtained. Amidic thiosemicarbazones containing different heterocyclic moieties were synthesized to evaluate the influence of these groups on the schistosomicidal and antichagasic activity. At the end, it was observed that substituting the 1,3,4-thiadiazolic ring with the thiosermicarbazone group didnt contribute to the antichagasic activity; but enhanced the drug effect against Schistosoma mansoni. Substituting the imidazole by the furan also worsened the antichagasic activity, but improved the schistosomicidal activity. However, the substitution of the imidazole by thiophene worsened the activity against both parasites. Compounds without the nitro group were the least effective of all the synthesized derivatives, indicating that this group possibly belongs to the pharmacophoric group. The formation of the amides, designed to act as prodrugs, produced promising antichagasic results, where 1-methyl-2-(5- acetamide-1,3,4-thiadiazole)-5-nitroimidazole (3) had an IC50=0,375 µM, and 1-2-(5-propionamide-1,3,4-thiadiazolyl)-5-nitroimidazole (5) had an IC50=2,085 µM. Further studies of inhibition against amastigote forms of Trypanosoma cruzi as well as in vivo studies are needed to validate the results obtained from both compounds.