Síntese, caracterização de complexos de Ag(I) com N-acil-hidrazonas: potenciais compostos micobactericidas

Abstract

Tuberculosis is a disease caused by the bacterium Mycobacterium tuberculosis that affects the whole society and that has been generating a large number of deaths due to population clusters, social inequality, migratory movement, and the appearance of strains resistant to first and second-line drugs, due to that is, several types of research are looking for the development of new drugs. Strategies have been used in research based on the development of metallic complexes, where a bioactive metal and organic ligand is used, in the case of N-acyl hydrazones derived from pyrazinamide, training to make use of the synergism effect. Thus, this work carried out syntheses and characterizations of N-acylhydrazones derived from Pyrazinamide, as well their respective silver(I) complexes, in 1:1 ratio (M:L). For the characterization of N-acyl hydrazones and their silver(I) complexes, spectroscopic techniques were used, Infrared spectroscopy (IR) and 1H, 13C and 15N-NMR (Nuclear Magnetic Resonance), elemental analysis measurements of Carbon, Hydrogen and Nitrogen (C, H and N) and thermal analysis – thermogravimetry and differential, by powder X-Ray Diffraction and Molar Conductivity. The use of the 15N-NMR spectra analysis, it was possible to suggest that the coordination of ligand to metal ion occurs throughout Nitrogen atoms of the Pyrazine ring (Nβ) and the imino group to [Ag(PZALD-1)]NO3 and [Ag(PZALD-2)]NO3 complexes, while the coordination occurs only by Nitrogen from the imine group in the [Ag(PZALD-3)]NO3 and [Ag(PZALD-4)]NO3 cases. An the homonuclear 1H 2D NMR spectroscopy was carried out to elucidate how configurations of the ligands in the complexes, in which they present geometric isomerism of E configuration. Based on this study, the perspective is to carry out biological tests of the ligands and their respective complex against Mycobacterium tuberculosis