A series of ten 1-[(5-nitrothenylidene)amino]azoles has been synthesized by the reaction of 5-nitrothiophene-2-carbaldehyde with 1-aminopyrazole, 1-aminoimidazole, 1- and 4- amino-1, 2, 4-triazoles, 1-aminoindole, 1- and 2-aminoindazoles, 1-aminobenzimidazole and 1- and 2-aminobenzotriazoles. Physical data, spectroscopic characteristics and biological properties of all the derivatives have been examined. The antiprotozoal activity has been tested against Trypanosoma cruzi, comparative to Nifurtimox (Lampit).