Vol. 6, Issue 9, Part C (2020)

Abstract
Uranyl complexes of Schiff bases derived from pyridine-2-carboxaldehyde and pyrazine-2- carboxylic hydrazone are reported and characterized based on elemental analyses, IR, solid reflectance, magnetic moment, molar conductance, and thermal analysis. The complexes are found to have the formula [(UO₂) LX₂] 3H₂O where X= CH₃OO^- or NO₃^-. The molar conductance data reveal that the metal chelates are non-electrolytic in nature. IR spectra shows that the ligand behaves in a bidentat manner utilizing azomethene nitrogen are carboxyl oxygen. From the magnetic and solid reflectance spectra, it is found that the geometrical structures of these complexes are octahedral and tetrahedral. The thermal behavior of these complexes shows that the hydrated complexes lose water molecule of hydration in the first step and is immediately followed by decomposition of the anions and ligand molecules in the subsequent steps. Ligands, in comparison to their metal complexes, were also screened for their antibacterial activity against bacterial species, E. coli, Pseudomonas aeruginosa, and Staphylococcus Pyogones, as well as fungi (Candida). The activity data show the metal complexes to be more potent antibacterial than the parent Schiff base.