Complexes of Co(II) with two new Schiff bases TEAB [2-hydroxy-4-{[2-oxo-2-(thiophen-2-yl)ethylidene]amino}benzoic acid] and TEPC [N-[2-oxo-2-(thiophen-2-yl)ethylidene]pyridine-3-carboxamide] have been synthesized and characterized with the help of elemental analysis, magnetic, mass,1H-NMR,13C-NMR, IR and electronic spectral data. IR spectra manifest the coordination of the ligand to the metal ion through the carbonyl oxygen, azomethine nitrogen and thienyl sulphur atoms. With the help of electronic spectral data various ligand field parameters were also calculated. All these studies reveal the distorted octahedral Co(II) complexes. Synthesized compounds have also been screened against some micro organismsviz, Escherichia coli, Proteus vulgaris, Aspergillus nigerandAspergillus flavuswith the help of ‘filter paper disc’ technique. It has been observed that the antimicrobial activities of metal complexes are higher than that of the free ligand.

Chlorine atoms of hexachlorocyclotriphosphazene were substituted with -NH.C2H5, -NH.CH2C6H5 and -OC2H5 to yield organotriphosphazene ligands. Anhydrous cobalt(II) chloride formed a number of addition complexes with these ligands in different stoichiometric ratios. On the basis of electronic and IR spectra, magnetic moment, conductivity meas­urements and molecular weight determination, structures of these complexes have been sug­gested. The complexes were screened for their antifungal activities against Aspergillus flavus and Aspergillus niger.

No abstract