Synthesis, characterization, antitumor activity of nickel(II) and cobalt(II) complexes of 2,2′-diamino-4,4′-bithiazole and their interaction with dGMP

New complexes, of bis(2,2′-diamino-4,4′-bithiazole)sulfate nickel(II) and bis(2,2′-diamino-4,4′-bithiazole)sulfate cobalt(II), have been prepared. The complexes were characterized by infrared and UV-Vis spectroscopy, ¹H NMR, elemental analyses and molar conductivity. The effect of these complexes on the DNA synthesis of sarcoma 180 cells has been studied by the technique of isotopic liquid scintillation. The results indicated that complexes show ability to inhibit DNA synthesis of the tumor cells. In order to provide a molecular basis for understanding the biological effects, the probe, [trans-en₂Os(²-H₂)](CF₃SO₃)₂ (en, ethylenediamine) as a monitor was first used to explore interaction of the complexes with 2′-deoxyguanosine-5′-monophosphate (dGMP).