Síntese e avaliação biológica de derivados pirazólicos

Abstract

This work describes the preparation, purification and characterization of 3,5- disubstituted pyrazoles, showing different substitution patterns in the aromatic rings present in the structure. Using four different synthetic methodologies, it was possible to obtain eighteen pyrazole derivatives. In addition, two more 1,3,5-trisubstituted pyrazoles was obtained from an N-alkylation reaction. Once purified, the structures of the compounds obtained were characterized by 1H and 13C Nuclear Magnetic Resonance (NMR), infrared spectroscopy (IR), melting point and elemental analysis (CHNS). NOESY experiments were carried out to determine the isomer formed in obtaining pyrazoles. The synthesized compounds were then evaluated for their cytotoxic activity against animal healthy cell and tumoral animal and human cells; antibacterial activity against gram-positive and gram-negative bacterial strains; antioxidant activity; antitubercular activity; and schistosomicidal activity. The pyrazoles tested did not demonstrate expressive toxic activity against the tested organisms, but they were also not toxic to normal cells, making them good candidates for tests against other pathologies. In addition to their biological role, pyrazoles also proved to be efficient when used as binders in bioinorganic chemistry, as well as when used as catalysts in CO2 fixation reactions. In addition to the planned pyrazoles, the synthetic intermediate hydrazones were also purified and characterized using the same techniques and, due to the biological importance shown by this class of compounds, they were also tested for their schistosomicidal activity. Although the tested compounds did not show toxicity to the tested organism, they were not toxic to normal cells, stimulating the continuation of the search for the biological potential of this class of compounds in different pathologies.