Retta, Negussie (PhD)Gebre, Mulu2018-06-212023-11-092018-06-212023-11-092000-06http://etd.aau.edu.et/handle/12345678/2511The condensation of o-phenylene diamines with a- carbonyl compounds results in the formation of a variety of quinoxalines. By suitable choice of a- carbonyl component (oxalic acid), quinoxaline-2, 3- dione has been prepared. The result obtained has been characterized and it is in well agreement with the results reported in literature. So far there are no reports on the condensation of quinoxaline-2, 3- dione with amines or polyamines. In this study a suitable amine group, 1, 3-diatninopropane, has been selected. A new oxygen nitrogen chelating system, which is a condensed product of quinoxaline-2, 3-dione with 1, 3-diaminopropane has been isolated and characterized by elemental analysis,electronic and IR spectral data. New N, N’- bis (3- quinoxaline- 2- one) diaminopropane (BQxDP) complexes of cobalt (II), nickel (II), copper (II), zinc (II), cadmium (II) and mercury (II) have been prepared and characterized by elemental analysis, conductance, IR and electronic spectral data. The ligand acts as neutral ONN donor system in cobalt (II), nickel (IT) and copper (II) complexes. In case of zinc (II), cadmium (II) and mercury (II) complexes it acts as ONNO donor system.From the analytical and electronic spectral data all the complexes except copper (II) have been found to be octahedral in geometry. Electronic spectral data supports the formation of a distorted octahedral geometry for copper (II) complex . The ligand, metal complexes and related compounds have subjected to preliminary studies for antibacterial activity against Bacillus T.I. and E. Coli. In general the ligand and most ofthe metal complexes are inactive. Only Cd (II) complex shows inhibitory activity against gram +ve Bacillus T.I. at 100 pg/mL concentration. Further studies are necessary to draw worthwhile conclusions.enMetal Complexes of a New Nitrogen Heterocyclic Chelating systemThesis