Study of Binary and Ternary Complexes of Co(II), Ni(II), Cd(II), Fe(III), and UO2(II) Complexes of Amino Carboxylic Acid Derivatives and Pyridine, Synthesis, Spectroscopic Characterization, Thermal Investigation and Biological Activity

Abstract

TWO Schiff base ligands of organic acid moity, vis., N- (2- carboxyphenyl) salicylideneimine, (H 2L1) and N-(2-carboxyphenyl) thiopheneimine, (HL2) have been synthesized by the interaction of salicylaldehyde and 2- thiophenecarboxaldehyde with 2- amino benzoic acid.Co (II), Ni (II), Cd (II), Fe (III) and UO2 (II) complexes of these ligands have been prepared. Also, the ternary complexes were prepared by using pyridine (Py) as a secondary ligand. All synthesized compounds were identified and confirmed by elemental analysis, molar conductance, IR, 1HNMR, UV-Vis, mass spectra, magnetic measurements, and thermal analysis. The molar conductance data reveal that these complexes are non electrolytic, 1:1 and 1:2 electrolytic nature of the metal complexes. The ligands are coordinated to the metal ions in a terdentate manner with ONO/ONS donor sites of the carbonyl oxygen, azomethine nitrogen and phenolic oxygen or thiophenic sulphur. An octahedral structure is proposed for the prepared metal complexes. The thermal stability of the metal complexes is evaluated. The synthesized ligands, in a comparison to their metal complexes also were screened for their antibacterial activity against bacterial species, bacillus cereus, bacillus subtilis and Escherichia coli. The activity data show that some metal complexes to be more potent / antibacterial than the parent organic ligands against one or more bacterial species.

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