Synthesis, Characterization and In Vitro Cytotoxicity of Platinum (II) Complexes with Some Tetradentate Salen Ligands

A series of platinum (II) complexes of Schiff bases derived from various salicylaldehydes with ethylenediamine were synthesized and characterized by ESI-MS, NMR and IR. The results of ESI-MS and NMR spectra data showed that the separation of hydrogen from hydoxy group and different chemical shifts of typical bondings between ligands and platinum (II) complexes evidenced for coordination of Pt (II) and tetradentate ligands. The IR spectral studies indicated the binding sites of the salen ligands with Pt (II). Their photophysical properties studied by UV-vis and luminescent spectroscopies performed the photoactivity of investigated platinum (II) complexes. The obvious effect of electron-withdrawing and – donoring substituted groups at the same position of salicyl rings and the impact of methoxy at different position of salicyl rings to their photophysical properties were studied and compared to complex 1 without substituted group. The obtained complexes were screened for their in vitro antitumour activities against KB and MCF-7 human cancer cell lines. Complex 4 showed the best bioactivity for both KB and MCF-7 human cancer cells with IC50 1.92 μM