Thermal, kinetic, spectroscopic studies and anti-microbial, anti-tuberculosis, anti-oxidant properties of clioquinol and benzo-coumarin derivatives mixed complexes with copper ion

Abstract

A series of six Cu(II) complexes of clioquinol with benzo-coumarin derivatives have been synthesized. Physico-chemical, spectroscopic, and thermal properties of the complexes have been studied on the basis of infrared spectra, mass spectra, NMR spectra, electronic spectra, elemental analyses, and thermogravimetric analyses. The kinetic parameters such as order of reaction (n), energy of activation (E a), entropy (S*), pre-exponential factor (A), enthalpy (H*), and Gibbs free energy (G*) have been calculated using Freeman-Carroll method. All the compounds were screened for their anti-bacterial activity against Escherichia coli, Pseudomonas aeruginosa, Streptococcus pyogenes, Bacillus subtilis, and anti-fungal activity against Candida albicans and Aspergillus niger. Ferric-reducing anti-oxidant power of all complexes were measured. Also the compounds against Mycobacterium tuberculosis shows clear enhancement in the anti-tubercular activity upon copper complexation. Structural, spectroscopic, and biological aspects of ligands and its metal complexes have been studied on the basis of mass spectra, NMR, FT-IR spectrophotometry, and elemental analyses. Thermal behavior and kinetic properties of complexes were discussed. The structure of compounds has been monitored for their in vitro anti-microbial, anti-oxidant, and anti-tuberculosis activity.