Síntese e avaliação biológica de aminas e aminoalcoóis aromáticos e heteroaromáticos

Abstract

An increased number of bacteria and protozoa resistant to the usual chemotherapy has been observed. Thus, these drugs could become obsolete, making essential the development of new biologically active compounds. Among the various classes of antimicrobial and antiprotozoal compounds, amino alcohols and heterocyclic aromatic groups have been high lighted, as they are found in many drugs. Giving continuity to the ongoing studies conducted by our research group, in this work are described the synthesis of amines and amino alcohols by reductive amination of substituted benzaldehydes (p-octyloxy, p-methoxy and p-nitro benzaldehyde) and of 2-pyridil and 4- pyridil carboxaldehydes with monoethanolamine, 2-amino-2-methylproanol and octylamine. In the second part of the work compounds were synthesized from metronidazole, a substance with a broad spectrum of activity. The compounds were obtained by nucleophilic substitution of metronidazole mesylate with different amino alcohols and octylamine. After purification and characterization through the usual spectroscopic methods (1H NMR, 13C NMR and IR), the biologic properties of the obtained compounds were evaluated in vitro. The evaluation of the antibacterial activity was performed against gram-positive and gramnegative microorganisms, through the analysis of the halo of inhibition and of the minimum inhibitory concentration. The metronidazole derivatives are being evaluated for their antiparasitic properties. The results show that the antibacterial activity depends on lipophilicity, since all the compounds carrying the octyl chain were active.