| Summary: | The reaction between [PtCl<sub>2</sub>(L-L)] (L-L = dppe, dppp, dppb, dppf, Phen and Bipy) or [PtCl<sub>2</sub>(PPh<sub>3</sub>)<sub>2</sub>] with 1-benzyl-3-phenylthiourea (H<sub>2</sub>BPT) in a basic medium (CHCl<sub>3</sub>/EtOH) created new coordinated square planner Pt(II) complexes with [Pt(BPT)(L-L)] (<b>1</b>–<b>4</b>,<b>6</b>,<b>7</b>) and [Pt(BPT)(PPh<sub>3</sub>)<sub>2</sub>] (<b>5</b>) types. These complexes were fully characterized by analytical and spectroscopic techniques (i.e., IR, UV. Vis., <sup>1</sup>H, and <sup>31</sup>P NMR). The results indicated that the thiourea derivative ligand act as a dianion ligand bonded through both S and N atoms in a chelating mode or as a mono-anion ligand coordinated through a sulfur atom with Pt(II) ion. Cytotoxicity activity was performed by the MTT assay to determine anti-cancer activities against MCF-7 breast cancer cells. The study indicated that IC<sub>50</sub> values for MCF-7 cells were 10.96–78.90 µM. Additionally, the complexes [Pt(BPT)(dppe)] (<b>1</b>), [Pt(BPT)(PPh<sub>3</sub>)<sub>2</sub>] (<b>5</b>), and [Pt(BPT)<sub>2</sub>(Bipy)] (<b>7</b>) were investigated theoretically, where their quantum parameters were evaluated using the Gaussian 09 program using the theory of B3LYP/Def2TZVP//B3LYP/Lanl2dz. The calculation results confirmed the optimized structures of the complexes square planar geometry. However, the calculated bond lengths and angles showed a slightly distorted square planar geometry due to the <i>trans</i> influence of the sulfur atom. Additionally, complexes of [Pt(BPT)(dppe)] (<b>1</b>) and [Pt(BPT)(PPh<sub>3</sub>)<sub>2</sub>] (<b>5</b>) showed higher stability compared to [Pt(BPT)<sub>2</sub>(Bipy)] (<b>7</b>), which can be attributed to the higher back-donation of (<b>1</b>) and (<b>5</b>) complexes. Furthermore, among the three complexes, the [Pt(BPT)<sub>2</sub>(Bipy)] (<b>7</b>) complex possessed the lowest HOMO–LUMO gap, which may be a good candidate as the photo-catalyst material.
|
|---|