Synthesis, Spectroscopic Characterization, and Genotoxicity of a New Group of Azo-Oxime Metal Chelates

Abstract

A new azo-oxime ligand, 2-[(E)-(hydroxyimino)methyl]-4-[(E)-(4-nitrophenyl)diazenyl]phenol, (pxoxH(2)) (2), was prepared by condensation of hydroxylamminehydrochloride and 2-hydroxy5-[(4-nitrophenyl)diazenyl]benzaldehyde (1) with treatment of a solution of diazonium salt of p-nitroaniline and 2-hydroxybenzaldehyde in ethanol. The 6 coordination compounds, [Mn(pxoxH)(2)(H2O)(2)]center dot H2O (3), [Co(pxoxH)(2)(H2O) (2)]center dot 4H(2)O (4), [Ni(pxoxH)(2)(H2O)(2)]center dot 2H(2)O (5), [Cu(pxoxH)(2)]center dot H2O (6), [Zn(pxoxH)(2)]center dot 6H(2)O (7), and [Cd(pxoxH)(2)(H2O)(2)]center dot H2O (8), were prepared by reacting Mn(II), Ni(II) Cu(II), Co(II), Zn(II), and Cd(II) ions with the ligand. The structures of the compounds were elucidated from the elemental analysis data and spectroscopic studies. The azo-oxime metal complexes were also characterized by XRD, magnetic moment, molar conductivity, and thermal analyses. Elemental analyses of the chelates suggested that the metal to ligand ratio was 1:2. It was found that the ligand acts as a bidentate bending through the phenolic oxygen and nitrogen atom of the C=N-OH group similar to most oximes. Upon complexation with the ligand, the Cu(II) and Zn(II) ions formed square planar and tetrahedral structures, respectively, and the Mn(II), Ni(II), Co(II), and Cd(II) ions formed octahedral structures with 2 water molecules as axial ligands. Finally, the ligand and its complexes were assessed for their genotoxicity.