DNA Binding, Molecular Docking and Antimicrobial Evaluation of Novel Azo Dye Ligand and Their Metal Complexes

Abstract

In the present work, the synthesis of novel azo dye ligand 6-hydroxy-4-methyl-2-oxo-1-propyl-5-[(E)-1,3-thiazol-2-yldiazenyl]-1,2-dihydropyridine-3-carbonitrile (L) and its Cu(II), Co(II) and Ni(II) transition complexes were prepared. The newly formed compounds were characterized by elemental analysis, UV–Vis, FT-IR, 1H NMR, LC–MS, TGA and magnetic susceptibility measurement. The molar conductance indicates that all the metal complexes are non-electrolytic in nature Based on spectral data indicate square planar geometry was deduced for Cu(II) and Ni(II) complexes, Co(II) complex has tridentate chelation of ligand and produce an octahedral geometry around the metal ion. Additionally, the computational study has been performed using density functional theory (DFT) calculation was used to study the electronic structure of synthesized ligand and their complexes. The in vitro antimicrobial activity of the azo dye ligand and its complexes was tested against Gram +ve bacteria (Bacillus subtilis), Gram –ve bacteria (Escherichia coli), yeast (Candida albicans) and fungus (Aspergillus flavus). All the complexes showed enhanced biocidal activity compared to the free ligand. Moreover, azo dye ligand and its metal complexes have been studied for their antioxidant activity. The DNA-binding activity of metal complexes (1a–1c) was studied by electronic absorption spectroscopy and fluorescence spectroscopy. All the complexes bound to CT-DNA through an intercalation mode. Additionally, all the metal complexes act as good cleavage agents against the pBR322 DNA. The computer-aided molecular docking studies of metal complexes with the receptor of GlcN-6-P synthase showed that metal complexes are potent drugs for the target enzymes.