Synthesis, Characterization and &lt;i&gt;In Vitro&lt;/i&gt; Cytotoxicity of Platinum (II) Complexes with Some Tetradentate Salen Ligands

Quang Trung Nguyen

doi:10.11648/j.sjc.20190702.13

Abstract

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.

Highlights

The modern application of transition metal complexes as chemotherapeutic agents came from the discovery of cisplatin by Rosenberg et al in 1965 and this discovery opened a new gate of metal-based chemotherapeutic agents which have different kinetics and mechanism of action from those of conventional organic drugs [1]
Because of tetradentate salicylaldiminato Pt (II) complexes’ potential in chemotherapy for various human cancer cell lines, in this research we continue to study on Pt (II) complexes of tetradentate salicylaldimine ligands derived from various salicylaldehydes with ethylenediamine and estimate their photophysical properties and in vitro cytotoxicity for KB and MCF-7 human cancer cell lines as well
Methoxy group at different positions of salicyl ring could affect to Pt (II) complexes’ emission wavelengths

Summary

Introduction

The modern application of transition metal complexes as chemotherapeutic agents came from the discovery of cisplatin by Rosenberg et al in 1965 and this discovery opened a new gate of metal-based chemotherapeutic agents which have different kinetics and mechanism of action from those of conventional organic drugs [1]. Bioinorganic and medicinal chemists are exploring different strategies to overcome these obstacles, which includes targeted delivery of clinical drugs [4] and design of new novel platinum and non-platinum metal complexes which have different structural features and reactivities [5]. Schiff base complexes are used as model molecules for biological oxygen carrier systems. Some of these complexes have applications in analytical fields [8]. Because of tetradentate salicylaldiminato Pt (II) complexes’ potential in chemotherapy for various human cancer cell lines, in this research we continue to study on Pt (II) complexes of tetradentate salicylaldimine ligands derived from various salicylaldehydes with ethylenediamine and estimate their photophysical properties and in vitro cytotoxicity for KB and MCF-7 human cancer cell lines as well

Results

Discussion

Conclusion