Abstract

This study reported the synthesis of the new ligands, 3,4-methylenedioxybenzyl-S-benzyldithiocarbazate (L1), p-chloro-benzyl-S-benzyldithiocarbazate (L2) and 2,6-dichlorobenzyl-S-benzyldithiocarbazate (L3).  These three schiff base type ligands were respectively obtained by means of the reaction of 3,4-methylenedioxybenzaldehyde, p-chlorobenzaldehyde and 2,6-dichlorobenzaldehyde with S-benzyldithiocarbazate, at molar ratio 1:1. The respective Cu(II) complex C1, C2 and C3 were synthesized by the reaction of L1, L2 or L3, with CuCl₂.₂H₂O, at molar ratio 1:1. The chemical identification of ligands and respective complexes was established through spectroscopic data (FT-IR, UV-Vis and ¹H NMR). The ligand and complexes were subjected to in vitro radial diffusion assays against the gram-negative bacteria Escherichia coli and gram-positive Staphylococcus aureus and the fungus Candida albicans and Saccharomyces cerevisiae, with good results for some of these compounds. Due to its promising antimicrobial property, complex C1 was subjected to EPR analyses aiming to establish its conformational structure. The prediction of biological activities of ligands and complexes were evaluated through the simulation carried out in silico using the web tools PASSonline and ChemMapper.

Key words: Aryl-S-benzyldithiocarbazate, Cu(II) complexes, antimicrobial activity, PASSonline, ChemMapper