Synthesis, physicochemical characterization, exploration of biological potential and DFT study of di-and tri-organotin(IV) carboxylate derivatives

Here in this article we are reporting six newly prepared di- and tri-organotin(IV) complexes derived from 2-(2-((4-bromo-2-methylphenyl)amino)-2-oxoethoxy)acetic acid that were characterized by the FT-IR, ¹H & ¹³C-NMR, CHN analyses and single crystal X-ray crystallography. The solution state geometry obtained from NMR data using coupling constants (¹J[¹¹⁹Sn-¹H] and ²J[¹¹⁹Sn-¹³C]) as well as C-Sn-C angle indicate the 5- and 6-coordination environment around the Sn center for tri- and di-organotin(IV) complexes, respectively. The X-ray crystallographic data of complexes 1 and 3 revealed a five-coordinated distorted trigonal bipyramidal geometry with monodentate behavior of the carboxylate ligand. The solid state FT-IR data also confirm of monodentate nature of the carboxylate moiety for the triorganotin(IV) derivatives (1-3) and bidentate for the diorganotin(IV) derivatives (3-6). The HOMO-LUMO study indicates that an intermolecular charge transfer behavior is observed in the screened compounds. The higher ionization energy (6.61-6.74 eV) and smaller electron affinity values (0.74-0.97 eV) of HL and complexes 1-6, demonstrate their significant thermal stability and their ability to attract electrons. The total reducing power for complex 3 was maximum while the total antioxidant capacity for complexes 2 and 5 was highest among the studied compounds. Complex 6 has the highest % scavenging activity against DPPH. Complex 2 has shown maximum hemolysis of 78.69 among the tested compounds. Based on the achieved results, this study provides new insights for further development of organotin derivative as potential drug candidates.