Luminescent Platinum(II) Complexes Featuring Innocent Pyridine-2-aldoxime Ligand: Synthesis, Characterization, and Exploration of Their In Vitro Cytotoxicity Properties

Three new Pt(II) complexes (Pt1-Pt3) of general formula [Pt(C^N)(pyrald)] {where C^N = 2-phenylpyridine (ppy), 2-(2,4-difluorophenyl)pyridine (F₂ppy) and dibenzo[a,c]phenazine (phthquinox)} were synthesised to explore the possibility of non-innocent behavior of coordinated pyridine-2-aldoxime (pyrald) and metallodrug properties of new complexes. Pt1-Pt3 were prepared in mild conditions and purified using the column chromatographic method. The complexes were thoroughly characterized by different spectroscopic and analytical techniques. The anticancer properties of the complexes (Pt1-Pt3) were explored against two breast cancer cell lines, MCF-7 and MDA-MB-231 and the results revealed the inhibition of cancer cell proliferation at very low concentrations of all the complexes. Experimentally, the interactions of Pt1-Pt3 with DNA were also evaluated using electrophoresis techniques. TD–DFT calculations were performed on these new complexes for insightful analysis of their electrochemical and optical properties.