Coumarin complexes as antimicrobial and antituberculosis agents

The transition metal complexes bearing coumarin and 1,10-phenanthroline were synthesized. Neutral bidentate ligands as well as all transition metal complexes were studied on the basis of mass spectra, NMR 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 bonding of ligand toward metal ion. Furthermore, complexes investigated by means of thermogravimetry, electronic spectra and magnetic measurements. TGA study 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 employed strains have been found compared to its free ligands.