Zinc(II) complex: Spectroscopic, physicochemical calculations, anti-inflammatory and in silico molecular docking studies

Abstract

As a continuation of the work in the present article, we described the spectroscopic and physicochemical properties of the synthesized Zn(II)-2-amino-3-pyridinecarboxaldehyde complex was investigated experimentally and theoretically. The zinc(II) complex was optimized with B3LYP and B3PW91 functional with 6–311++G(d,p) basis set. Fourier transform infrared spectrum of zinc(II) complex was recorded in the spectral range 4000–400 cm−1 and Raman counterparts were measured in the spectral region 4000–50 cm−1. The experimental FTIR and Raman results are compared to theoretical geometrical parameters. The rms error between experimental and theoretical vibrational frequencies of the titled compound was found to be 8.9 cm−1. The HOMO-LUMO energy gap demonstrates the compound is highly chemically reactive. The Natural Bond Orbital (NBO) and Quantum Theory of Atoms in Molecules (QTAIM) analyses were employed to obtain a precise picture of the conjugative and hyper conjugative interactions within the structure of the investigated molecule. Additionally, zinc(II) complex was also screened for their anti-inflammatory activity, using the carrageenan-induced rat paw edema method. The investigated complex exhibited significant anti-inflammatory potencies compared to standards. Furthermore, the compound was also assessed for their molecular docking studies against protein receptor cyclooxygenase COX-2 (PDBID: 5IKT) and showed their binding energy value of −7.98 kcal/mol, towards the anti-inflammatory activity.