New Tin(IV) Schiff base complexes: synthesis, characterization and antibacterial investigation, docking and theoretical studies

Abstract

Organotin(IV) complexes with the formula [RSn(H2L)] (where R = Me (1), Ph (2) and. n-Bu (3), H2L = 2,2′-((1E,1′E)-(naphthalene-1,8-diylbis(azanylylidene))bis(methanyl-ylidene))dibenzoic acid) have been produced via the reaction of organotin(IV) salts with H2L. Wholly the complexes have been studied via CHN analyses, FT-IR and UV–vis 1HNMR and mass spectral studies. The spectroscopic data of the ligand and its corresponding complexes (1–3) revealed that the Schiff base chelated to the tin metal ion in a bidentate manner through NN atoms (nitrogen atoms of azomethine group). Around tin atom, hexacoordinated geometry was exhibited. All the complexes were electrolytes except complex 2 is nonelectrolyte. Thermal decomposition of the complexes using thermogravimetric analysis under nitrogen showed that the thermal degradation of the complexes (1–3) occurred between 200 and 700 °C. The Schiff base tin(IV) complexes (1–3) were tested in vitro for their ability to suppress the growth of several bacteria strains. It was observed that the complexes were more effective at killing bacteria than the Schiff base ligand. Density functional calculations were performed to explain the structure and reactivity of the compounds. MOE 2008 was used headed for screen potential drugs with molecular docking by the protein sites of new coronavirus, Escherichia coli, Pseudomonas aeruginosa and crystal structure of MAOB. The study was constructed to molecular docking without validation through MD simulations.