Synthesis, Characterization and Antibacterial Activity of Semicarbazide Based Schiff Bases and their Pb(II), Zr(IV) and U(VI) Complexes

Schiff bases are compounds with the general structure R2C=NR’. They can be prepared by the condensation of the primary amines with carbonyl compounds. In this paper, we have synthesized new Schiff base ligand (L) by reacting semicarbazide with 2-acetylthiophene in ethanol solvent and its metal complexes have also been synthesized by using Zr4+, Pb2+ and U6+ ions. Schiff bases of semicarbazide are often having promising biological activities like anti-inflammatory, antidepressant, antiglycation, antibacterial, etc. Schiff base ligand and metal complexes were characterized and have shown appropriate results when analyzed on UVVis., NMR, FT-IR and antibacterial activities. They were tested against gram- negative [E. Coli. (MTCC No: 452)] and gram- positive [Bacillus sp (MTCC No: 297)] bacterial strains by using Kirby-Bauer’s method. Schiff base complexes of Zirconium [Zr(L)4]Cl2] and lead [Pb(L)2]Cl2] were found to be more active against both bacterial strains having a zone of inhibition 11.14 ± 0.2 10.23 ± 0.5 mm and 12.02 ± 0.3 11.05 ± 0.3 mm on E. Coli. and on Bacillus species respectively.