Synthesis, crystal structure and antimicrobial studies of chlorido(dimethylsulfoxide-κS)(pyrrolidinedithiocarbamato-κ2S,S/)platinum(II)

In vitro and In vivo Studies of Potential Anticancer Agents of Platinum(II) Complexes of Dicyclopentadiene and Dithiocarbamates

Three platinum(II) complexes of dicyclopentadiene (DCP) and dithiocarbamates (DTC), namely, [Pt(η4-DCP)(Me2DTC)]PF6 (1), [Pt(η4-DCP)(Et2DTC)]PF6 (2) and [Pt(η4-DCP)(Bz2DTC)]PF6 (3) [Me2DTC = dimethyldithiocarbamate, Et2DTC = diethyldithiocarbamate, and Bz2DTC = dibenzyldithiocarbamate] were prepared and characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy. The spectroscopic data indicated the coordination of both DCP and dithiocarbamate ligands to platinum(II). The solution chemisty of complex 1 revealed that the complexes are stable in both DMSO and 1:1 mixture of DMSO: H2O. In vitro cytotoxicity of the complexes relative to cisplatin was tested using MTT assay, against CHL-1 (human melanoma cancer cells), MDA-MB-231 (breast cancer cells), A549 (lung cancer cells), and B16 (murine melanoma cancer cells). The antiproliferative effect of all three prepared complexes was found to be significantly higher than cisplatin. Furthermore, flow cytometric analysis of complex 1 showed that the complex induced apoptosis, oxidative stress, mitochondrial potential depolarization and cell cycle arrest in a concentration-dependent pattern in the CHL-1 cells. Confirmation of apoptosis via gene expression analysis demonstrated down-regulation of anti-apoptotic genes and up-regulation of pro-apoptotic genes in the CHL-1 cells. Wound healing assays also lent support to the strong cytotoxicity of the complexes. In vivo studies showed a significant reduction of tumor volume at the end of the experiment. In addition, the drug did not change the weight of the mice. In conclusion, complex 1 inhibited cell proliferation in vitro and reduced tumor growth in vivo.

Dithiocarbamate Complexes of Platinum Group Metals: Structural Aspects and Applications

The incorporation of dithiocarbamate ligands in the preparation of metal complexes is largely prompted by the versatility of this molecule. Fascinating coordination chemistry can be obtained from the study of such metal complexes ranging from their preparation, the solid-state properties, solution behavior as well as their applications as bioactive materials and luminescent compounds, to name a few. In this overview, the dithiocarbamate complexes of platinum-group elements form the focus of the discussion. The structural aspects of these complexes will be discussed based upon the intriguing findings obtained from their solid- (crystallographic) and solution-state (NMR) studies. At the end of this review, the applications of platinum-group metal complexes will be discussed.