Synthesis and preliminary in vitro cytotoxic activity of Pd(II) complexes including Salen- or Salphen-Ligands

The synthesis of a series of Pd(II) (Pd-1-3) complexes including either salen or salphen ligands is described. All complexes were fully characterised by standard spectroscopic techniques. Complex Pd-3 was also characterised by single-crystal X-ray diffraction analysis, revealing the palladium center in Pd-3 to be in distorted square planar environment. In addition, the determination of the in vitro cytotoxic activity of the palladium complexes Pd-1-3 was evaluated against five human cancer cell lines including human glioblastoma (U-251), human prostatic adenocarcinoma (PC-3), human lung adenocarcinoma (SKLU-1), human gingival fibroblast (FGH) and human mammary adenocarcinoma (MCF-7). Being complex Pd-2 the best of the series when compared to cisplatin against human prostatic adenocarcinoma (PC-3) with a half maximal inhibitory concentration (IC50) of 3.8 +/- 0.4 mu M. These results were complemented with docking calculations.