Nitrogen heterocycles are a part of a special group of organic substances found in many biologically active natural and synthetic products with properties pharmacologically relevant. The synthesis and spectroscopic characterization of tetrahydroquinolines (THQs) and isoxazole are shown. These compounds were evaluated for their in vitro antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Acinetobacter baumannii. With the purpose of evaluate the structural features in the antibacterial activity, in the present work, some substituents such as: methyl, methoxy and hydrogen in different positions on the THQ ring are reported.