Azo-azomethine ligands with N2O2 donor atom sets and their binuclear UO2(II) complexes: synthesis, characterization and biological activity

Two azo-azomethine ligands with N2O2 donor atom sets and their binuclear UO2(II)-complexes were synthesized for therapeutic uses. The ligands were derived from the condensation of 4-(4-hydroxy-3-formy1-1-ylazo)-N-pyrimidin-2-yl-benzenesulfonamide with ethylenediamine and 1,6-hexanediamine. The prepared ligands and their bi-homonuclear uranyl complexes were characterized by thermal analyses (TGA & conventional method), vibrational, electronic, H-1 NMR, and mass spectra as well as by different physicochemical techniques. The active coordination centers in the ligands and the geometrical arrangement of the complexes were investigated using the spectral data. Molar conductance measurements in DMSO solution denoted that the complexes are non-electrolytes. The investigated complexes and ligands were screened in vitro for their antimicrobial activity against fungi (Aspergillus flavus and Candida albicans), gram-positive bacteria (Staphylococcus aureus) and gram-negative bacteria (Escherichia coli). It was observed that the complexes are more potent fungicides and bactericides than the ligands.