Biscoumarin and their transition metal complexes

The effort summarized preparation of N2O2 donor mixed ligand metal complexes containing biscoumarin with 1,10-phenanthroline (Ph). Structural and spectroscopic properties of neutral bidentate ligands as well as all complexes were studied on the basis of mass spectra, NMR (1H and 13C) spectra, FT-IR spectrum and elemental analyses. Mass spectral data confirm the structure of ligands as indicated by the molecular ion peak (M+) corresponding to their molecular weight. IR spectral data suggest tetra-coordinated N2O2 bonding of ligand toward metal ion. Furthermore, complexes investigated by means of thermogravimetry, electronic spectra and magnetic measurements. TGA along with electronic spectra and magnetic measurement indicates octahedral geometry of complexes. Antimycobacterial screening of ligand and its copper compound against Mycobacterium tuberculosis shows clear enhancement in antitubercular activity upon metal complexation. Also good antimicrobial activities of the complexes against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Salmonella typhus, Aspergillus niger, Candida albicans and Aspergillus clavatus have been found compared to its free ligands.