Integrated quantum chemical calculations, predictive toxicity assessment, absorption, distribution, metabolism, excretion and toxicity profiling and molecular docking analysis to unveil the therapeutic potential of non-oxovanadium(IV) and organotin(IV) complexes targeting breast cancer cells

In this work, theoretical calculations of o-phenylphenol-based non-oxovanadium(IV) and organotin(IV) complexes, previously prepared and reported by our group, have been carried out by density functional theory (DFT). Density functional theory quantum chemical computations were used to explore the structural and spectroscopic characteristics of the complexes in this study. The inhibitory nature of complexes were revealed via molecular docking research, which were performed against selected breast cancer cell proteins, 5NWH and 3HB5. The optimization and stability of complexes 1–6, were conducted using optimized DFT/B3LYP/6–311++G (d, p) level. Simulated computations of the molecular electrostatic potential surface were also performed to analyze the reactive behavior of the non-oxovanadium(IV) and organotin(IV) complexes. The stability and molecular reactivity of the molecules were computed using the HOMO-LUMO energies, energy gap, chemical potential (μ), electronegativity (χ), hardness (η), and softness (S) values. In silico analysis through molecular docking, ADMET properties and toxicity evaluation was used to assess its anticancer activity, drug-likeness property and toxicity. The binding constant value, evaluated from molecular docking, was found to be very promising, −10.1 kcal mol⁻¹ observed for vanadium complex 5 and the complexes were found to exhibit inhibition constant as low as 0.0378 μMol. Root-mean-square deviation (RMSD) has been carried out to validate molecular docking studies, which have been found to be below 2.0 Å for the complexes, indicating successful docking of the ligand-protein complex by the program. The complexes, evaluated for their toxicity behavior in terms of Lethal Dose, based on Globally Harmonized System (GHS), have been found to be chemical safe falling under the category III and V and hence can find use as future metallo-based drugs.