Abstract

New series of mixed ligand complexes of Mn(II), Co(II), Ni(II) , Cu(II) , and Hg(II) ions were prepared in two general formula [ M (L1)(L2)2]Cl , and [M (L1)2(L2)2] for each ion with E-5-((4-nitro phenyldiazanyl)quinoline-8-ol (L1) as primary ligand , and imidazole molecule (L2) as a secondary ligand . Free ligands and their complexes characterized via MS , UV-Vis. , FTIR , 1HNMR, Magnetic suscbtibility, and Molar Conductivity . The results indicating the octahedral geometry for all compounds with [M(L1)2(L2)2] formula while the complexes which have general formula [ M(L1)(L2)2]Cl articulate tetrahedral geometry except [ Cu(L1)(L2)2]Cl which has square planer geometry . (L1) ligand behaved as bidentate through nitrogen atom and oxygen atom of hydroxyl group in the basic medium whereas imidazole coordinated through nitrogen (3) as a neutral monodintate ligand. Antibacterial efficiency of compounds were tested against (Enterococcus faecalis , Staphylococcus aureus, Escherichia coli, Pseudomonas aeroginosa, Proteus mirabilis and Klebsiella pneumoniae) multi-drug resistant bacteria (MDR). All compounds appeared significant efficacy contra MDR bacteria, but ligand L1 appeared maximum inhibition zone and anti-bacterial efficacy contra all MDR bacteria while the minimum inhibition zone was marked in ligand L2 antibacterial efficacy. The complexes generally have high antibacterial activities in gram +ve bacteria contrasted to gram -ve bacteria, where Hg (II) ion complexes showed higher biological efficacy on all bacteria than other mixed ligand complexes of other ions. Ni (II) ion complexes showed lower antibacterial activity compare to other metal complexes.