Synthesis, spectroscopic, DFT and in vitro biological studies of vanadium(III) complexes of aryldithiocarbonates

Vanadium(III) tris(dithiocarbonates), [(ROCS₂)₃V] (R=o-, m-, p-CH₃C₆H₄ and 4-Cl-3-CH₃C₆H₃) and donor stabilized addition complexes [(ROCS₂)₂V(Cl)·L] [L=NC₅H₅ or P(C₆H₅)₃] were synthesized and characterized by elemental analyses, IR, mass, TGA/DTA, SEM magnetic susceptibility and heteronuclear NMR (¹H, ¹³C and ³¹P) spectroscopic studies. The cytotoxicity of the complexes was measured in vitro using the cultivated human cell lines. In addition, the antioxidant activities of the ligands and its vanadium complexes were also investigated through their scavenging effect on DPPH radicals. The antimicrobial activity of ligands and some complexes has been conducted against three bacterial strains and fungus. The density functional theory (DFT) calculations of ligands and vanadium complexes were performed by the DFT/B3LYP/LANL2DZ method to obtain the optimized molecular geometry, vibrational frequencies, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO), thermodynamic properties and various other quantum-mechanical parameters.