Doubly end-on azido bridged mixed-valence cobalt trinuclear complex: Spectral study, VTM, inhibitory effect and antimycobacterial activity on human carcinoma and tuberculosis cells

• CoII/CoIII-(2-[{[2-(dimethylamino)ethyl]imino}methyl]-6-methoxyphenol).
• Doubly azido-bridged Co trinuclear complex.
• It is noteworthy that the CoIII atoms are diamagnetic in nature where as the central CoII atom behaves paramagnetically.
• The complex decreases the cell population growth on human carcinoma cells.
• Displays efficacy on the mycobacterial strains of human tuberculosis cells.

Doubly end-on azido-bridged mixed-valence trinuclear cobalt complex, [Co3(L)2(N3)6(CH3OH)2] (1) is afforded by employing a potential monoanionic tetradentate-N2O2 Schiff base precursor (2-[{[2-(dimethylamino)ethyl]imino}methyl]-6-methoxyphenol; HL). Single crystal X-ray structure reveals that in 1, the adjacent CoII and CoIII ions are linked by double end-on azido bridges and thus the full molecule is generated by the site symmetry of a crystallographic twofold rotation axis. Complex 1 is subjected on different spectral analysis such as IR, UV–vis, emission and EPR spectroscopy. On variable temperature magnetic study, we observe that during cooling, the χMT values decrease smoothly until 15 K and then reaches to the value 1.56 cm3 K mol−1 at 2 K. Complex 1 inhibits the cell growth on human lung carcinoma (A549 cells), human colorectal (COLO 205 and HT-29 cells), and human heptacellular (PLC5 cells) carcinoma cells. Complex 1 exhibits anti-mycobacterial activity and considerable efficacy on Mycobacterium tuberculosis H37Rv ATCC 27294 and H37Ra ATCC 25177 strains.

Doubly azido-bridged trinuclear cobalt complex, [Co3(L)2(N3)6(CH3OH)2] (1) is synthesized where L = NMe2CH2CH2NCH(OH)(OMe)C6H3 in moderate yield. The Co atoms adopt a distorted octahedral geometry. Complex 1 inhibits the cell growth of human carcinoma cells and exhibits anti-mycobacterial activity on human tuberculosis cells.Figure optionsDownload as PowerPoint slide