Synthesis, crystal structural description, DNA binding, molecular docking, and anticancer evaluation of the novel platinum(IV) supramolecular complex

A novel platinum(IV) supramolecular complex; [PtCl₂(2,2'-bipy)₂](PtCl₆) was synthesized in aqueous acetonitrile solution at ambient temperature with constant stirring. The structure was confirmed by elemental analysis, FT-IR, UV-vis, NMR spectroscopy, and single-crystal X-ray diffraction, revealing a unique distorted octahedral geometry and a three-dimensional network stabilized by hydrogen bonding and π-π stacking. DNA binding studies, including electronic absorption titration and viscometry, indicated a groove binding mechanism with a binding constant (K_b) of 5.00 × 10⁶ M^-1. Molecular docking with DNA (PDB ID: 1BNA) and cancer-related proteins (PDB codes: 3ig7, 3eqm, 4fm9) supports these interactions, while in vitro anticancer assays demonstrated potent cytotoxicity with IC₅₀ values of 41.37 μM for HepG2, 47.62 μM for HCT116, and 73.90 μM for MDA-MB-231 cells, outperforming cisplatin in selectivity. This study not only advances our understanding of structure-activity relationships in platinum-based complexes but also highlights the potential of this complex as a promising candidate for developing more effective and less toxic anticancer agents.