Shedding Light on the Hydrolysis Mechanism of cis, trans-[Ru(dmso)4Cl2] Complexes and Their Interactions with DNA-A Computational Perspective.

Using several computational tools such as density functional theory analysis, docking, and MD simulations, we performed a study on cis, trans-[Ru(II)(dmso)4Cl2] complexes, which have therapeutic potential as antimetastatic agents, and their association with DNA. Kohn-Sham energy decomposition analysis reveals that dmso ligands have much smaller interaction energies compared to the chlorido ligands, and their substitution by aquo ligands induces an extra stabilization of the other metal-ligand bonds. Once the complex is hydrolyzed, the aquo ligands have the weakest interactions to the metallic center and therefore are more labile for substitution by a DNA atom. Molecular docking and molecular dynamics were employed to understand the complex preassociation to DNA, pointing to a higher affinity of the hydrolyzed complexes, as well as showing spontaneous binding events during the simulations. Our results are consistent with the experimentally available data that suggest a mechanism in which the complexes are quickly hydrolyzed in solution, before forming cross-links with the DNA molecule. We present a set of methods that could be used to optimize these complexes computationally, aiding in the development of new drugs based on transition metals.