Synthesis, characterization, DFT and docking studies of tributyltin(IV) complex of 2-{4-hydroxy-3-[(2-carboxyphenylimino)methyl]phenylazo} benzoic acid

A tributyltin(IV) complex was prepared by reacting bis-tributyltin(IV) oxide with 2-{4-hydroxy-3-[(2-carboxyphenylimino)methyl]phenylazo}benzoic acid in a 1:1 metal-ligand ratio. The complex was characterized by elemental analysis, UV-Vis, IR,1H and 119Sn NMR spectroscopy and mass spectrometry techniques. The 119Sn NMR study of the complex indicated the presence of two tin centers in a similar chemical environment and the complex exhibited a five-coordinate trigonal bipyramidal geometry in the solution phase. The molecular ion peak in the EI-MS spectrum of the complex revealed its molar mass. The optimized geometry of the complex was predicted by a DFT calculation. The in vitro antifungal activity of the complex was studied against four fungal species with respect to the standard drug Amphotericin-B. A molecular docking study was also carried out to understand the mode of interaction of the complex with the active side of the enzyme present in fungal species.