Crystal growth, structural and spectroscopic characterization, antimicrobial activity, DNA cleavage, molecular docking and density functional theory calculations of Zn(II) complex with 2-pyridinecarboxylic acid

Abstract

A Zn(II) complex with 2-pyridinecarboxylic acid was prepared, and its crystal structure characterization was carried out using X-ray diffraction analysis. The spectroscopic properties of the Zn(II) complex were determined by means of Fourier transform infrared, Raman and UV-visible spectroscopic techniques. The coordination sphere for the central Zn(II) ion was found to be a distorted octahedron. The CO, CC and CN stretching vibrations were found highly active and strong, leading to intramolecular charge transfer within the Zn(II) complex. Density functional theory calculations were carried out to provide further understanding of structural, spectroscopic and nonlinear optical properties of the complex. The occurrence of hydrogen bonding interactions in the Zn(II) complex was explained by natural bond orbital analysis. According to obtained hyperconjugative interaction energies, metal-ligand charge transfer interactions occur in the Zn(II) complex. The antimicrobial activities were determined against standard Gram-positive and Gram-negative bacterial strains and yeasts using the minimum inhibitory concentration method. Having a significant effect against Candida albicans and Saccharomyces cerevisiae is important in that the complex can be used as a new antifungal agent. The calculated free binding energy of the interaction of the Zn(II) complex with DNA was found to be 6.72kcalmol(-1), indicating a high binding affinity between the complex and DNA.