Investigation on ternary complex formation between maltol and dipeptides with CoII , NiII and ZnII; Potentiometric, synthetic and antibacterial studies

Department of Chemistry, Nizam College, Osmania University, Basheerbagh, Hyderabad-500 001, India

E-mail : ettaiah.p@gmail.com

Manuscript received 05 July 2011, accepted 17 October 2011

The formation constants of mixed ligand complexes of Co^II , Ni^II and Zn^II with maltol (mal) and dipeptides viz. glycylglycine (GG), glycylvaline (GV), glycylleucine (GL) and glycylisoleucine (GIL) were determined pH metrically by employing algebraic method. The UV-Visible, IR and Mass spectra of isolated solid metal complexes of Ni^II inferred the formation of corresponding ternary complexes. The complexes have been screened for antibacterial activity and the results are compared with the activity of the free ligands. The observed increased antibacterial activity evident from these studies in ternary complexes than in corresponding free ligands suggests more lipophilicity of metal complexes to act on bacterial cell.