Structural characterization of cobalt(II) complexes of an N,O donor Schiff base and their activity on carcinoma cells

2-[{[2-(Dimethylamino)ethyl]imino}methyl]-6-methoxyphenol (LH) is a potential tetradentate monoanionic N2O2 chelator; however, this precursor coordinates to cobalt(II) centres in two ways, as neutral bidentate-NO and as terdentate-N2O, along with a pseudohalide, like thiocyanate and azide, to afford [Co(LH)2(NCS)]NO3 (1) and [Co(LH)2(N3)]NO3 (2), respectively. Both the complexes are characterized by spectroscopic (IR, UV–Vis) analysis, thermal and redox studies. The room temperature magnetic moments for 1 and 2 are 4.91 and 4.93 B.M, respectively. Single crystal X-ray diffraction analysis confirms the distorted octahedral geometry around Co(II). These two complexes (1 and 2) inhibit the cell growth of human lung carcinoma cells (A549 cells), human colorectal carcinoma cells (COLO 205 cells), human hepatocellular carcinoma cells (PLC5 cells) and human fibroblasts cells (NIH3T3). Complex 2 shows a higher inhibitory activity, with 46.00 ± 1.09 μM IC50 in human colorectal carcinoma cells (COLO 205 cells).

Two new octahedral cobalt(II) complexes containing a potentially tridentate Schiff base ligand were synthesized and characterized by spectral as well as thermal analysis and single crystal X-ray diffractometry. The inhibitory effects of both complexes on the cell population growth of different human cells were also investigated by MTT assays.Figure optionsDownload as PowerPoint slide