Synthesis and characterization of a new azo ligand and study of the biological activity, antioxidant and anticancer of the complex Au(III)

Several metal complexes were synthesized by coordinating the following ions: Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II), Au(III), and Ag(I), with a newly developed azo ligand obtained from 4-aminosulfonamide and 4-hydroxybenzaldehyde. The ligand structures and their transition metal complexes were characterized using various analytical techniques, including molar conductivity, element microanalysis (CHN), electronic spectroscopy, magnetic sensitivity, nuclear magnetic resonance, infrared spectroscopy, and mass spectrometry. The data indicate that the structures of these complexes is [[M(L)2(H2O)2, where M = Co (II), Ni (II), Cu (II), Cd (II), and Hg (II), [ML(H2O)2] where M = Ag(I), and [M(L)Cl2]] where M = Au(III). The magnetic susceptibility and electronic spectrum data for the complexes suggest an octahedral geometry for all except Au(III), which has a planar square geometry, and Ag(I), which has a planar square geometry. The infrared spectrum results show that the coordination sites are the azo-nitrogen atom and the farther azo-nitrogen atom. The azo ligand is a bidentate structure. The Au(III) complexes exhibit radical scavenging activity for DPPH, indicating potential and promising antioxidant activity. Additionally, the gold complex has shown anti-cancer effects by effectively killing lung cancer cells without affecting healthy cells. This is a significant finding in the potential use of gold complexes as highly selective treatments for lung cancer.