Two New Co(II) Complexes of Picolinate: Synthesis, Crystal Structure, Spectral Characterization, α-Glucosidase Inhibition and TD/DFT Study

Abstract

Co(II) complexes of 2-picolinic acid (picH) and 6-methylpyridine-2-carboxylic acid (6-MepicH) {[Co(pic)<inf>2</inf>·2H<inf>2</inf>O], (1), [Co(6-Mepic)(pic)·2H<inf>2</inf>O], (2)} were obtained and their structural and spectroscopic properties were investigated by XRD, FT–IR and UV–Vis spectroscopic techniques. The measurement of α-glucosidase inhibition of the synthesized complex 2 was fulfilled by IC<inf>50</inf> values. In order to provide further explanations about the electronic spectral properties, TD–DFT calculations in ethanol solvent and gas phase were carried out. HSEh1PBE/6-311G(d,p) level has been used to calculate the nonlinear optics (NLO) parameters and frontier molecular orbital (FMO) energies. The experimental refractive indexes and optical band gap energies for the Co(II) complexes have been obtained using FT–IR and UV–Vis spectra, respectively. Lastly, the molecular docking study of Co(II) complexes was carried out in order to demonstrate interactions between the synthesized complexes and target protein (the template structure S. cerevisiae isomaltase). Graphical Abstract: [Figure not available: see fulltext.]. © 2019, Springer Science+Business Media, LLC, part of Springer Nature.