An enolato-bridged dinuclear Cu(II) complex with a coumarin-assisted precursor: a spectral, magnetic and biological study

A new, phenoxo-bridged CuII dinuclear complex Cu2[(L)2(DMF)2] (1) was obtained by employing the coumarin-assisted tridentate precursor, H2L (2) , [benzoic acid(7-hydroxy-4-methyl-2-oxo-2H-chromen-8-ylmethylene)-hydrazide]. Complex 1 was systematically characterized by FTIR, UV-visible, fluorescence and EPR spectrometry. The single crystal x-ray diffraction anal. of 1 shows that the geometry around each copper ion is square pyramidal, comprising two enolato oxygen atoms belonging to different ligands (which assemble the dimer bridging the two metal centers), one imine-N and one phenolic-O atoms of the Schiff base and one oxygen atom from the DMF mol. The temp. dependent magnetic interpretation agrees with the existence of weak ferromagnetic interactions between the bridging dinuclear Cu(II) ions. Both the ligand and complex 1 exhibit anti-mycobacterial activity and considerable efficacy towards M. tuberculosis H37Rv ATCC 27294 and M. tuberculosis H37Ra ATCC 25177 strains. The cytotoxicity study on human adenocarcinoma cell lines (MCF7) suggests that the ligand and complex 1 have potential anticancer properties. Mol. docking of H2L with the enoyl acyl carrier protein reductase of M. tuberculosis H37Rv (PDB ID: 4U0K) was examd. and the best docked pose of H2L shows one hydrogen bond with Thr196 (1.99 Å). [on SciFinder(R)]