Synthesis, characterization, electrochemical behavior, and antimicrobial activities of aromatic/heteroaromatic sulfonylhydrazone derivatives

The aromatic/heteroaromatic sulfonylhydrazone derivatives as indole-3-carboxaldehyde methanesulfonylhydrazone (1), indole-3-carboxaldehydeethanesulfonyl hydrazone (2), thiophene-2-carboxaldehydeethanesulfonylhydrazone (3), 2-hydroxybenzaldehydeethanesulfonyl hydrazone (4), 2-hydroxyacetophenoneethanesulfonylhydrazone (5) and 2-hydroxy-1-naphth aldehydeethane sulfonylhydrazone (6) were synthesized by the reaction of sulfonic acids with aromatic/heteroaromatic aldehydes and characterized by using elemental analysis, H-1-C-13 NMR, LC-MS and IR spectra. The electrochemical behavior of the sulfonylhydrazones in DMSO at glassy carbon electrode was investigated using cyclic voltammetry, controlled potential electrolysis and chronoamperometry techniques. The number of electrons transferred, diffusion coefficient and standard heterogeneous rate constants were determined using electrochemical methods. Antimicrobial activities of the compounds 1-6 were tested against some microorganisms. The biological activity screening showed that compound 6 exhibited better activity than the others. Structure-activity relationship analysis of the sulfonylhydrazone derivatives was performed to explain the trend of activity with molecular descriptors. The indicator descriptors for compound 6 having naphtyl ring are the most important descriptos that are sensitive both to the size and electrophility of the molecules.