Synthesis and Characterization of Cobalt Metallo-Chemotherapeutics with Thiazole-Containing Ligands

Since the discovery of cisplatin, a highly potent metallo-chemotherapeutic, transition metal complexes have been of increasing interest. This is due, in part, to the tremendous success of cisplatin, as well as its problematic side effects caused by lack of specificity and broad toxicity. As such, the investigation into the cytotoxicity of complexes with first row transition metal centers are of interest due to their established biological relevance, including cobalt, the active site metal in Vitamin B12. The development of new biologically relevant transition metal complexes also includes careful discernment of the ligand frame. Here, we are reporting a set of three new cobalt-containing metal complexes with different thiazole-containing ligands. The synthesis and complete characterization of 6-methoxy-2-pyridine benzothiazolecobalt(II) chloride, 2-pyridine benzothiazolecobalt(II) chloride, and 6-[4-(methylthio)phenyl]-2-pyridine benzothiazolecobalt(II) chloride as well as the precursor ligands will be presented. Characterization includes NMR, UV/Vis, and IR spectroscopic analysis, elemental analysis, and single crystal X-ray diffraction.