Synthesis, Structure, DFT Calculations, and In Silico Toxic Potential of Ni(II), Zn(II), and Fe(II) Complexes with a Tridentate Schiff Base

The Schiff base ligand has been synthesized from 5-bromo-2-hydroxybenzaldehyde and ethyl 6-acetyl-2-amino-4,5,6,7-tetrahydrothieno[2,3-c]pyridine-3-carboxylate, and complexed with Ni(II), Zn(II), and Fe(II). Elemental analysis, spectral data and calculations on the DFT/UB3LYP/LANL2DZ level of the ligand and its metal(II) complexes have supported geometric and electronic characteristics of the compounds. Interactions of the products with 16 target proteins have been simulated. Kinetics stability, binding affinities (IC50), and toxic potential (TP) of the ligand-protein complexes have been approached with the aid of molecular simulation. The ligand has been identified as a compound of low toxicity.