Metal (III) and (II) coordination compounds of o- phenylenediamine, oxalic acid dihydrate and 8-hydroxyquinoline were synthesized for mixed ligand complexes and characterized using FT-IR, UV-Vis and mass spectra, atomic absorption, elemental analysis, electric conductance and magnetic susceptibility measurements. In addition, thermal behavior (TGA) of the metal complexes (1-6) showed good agreement with the formula suggested from the analytical data. The stoichiometric reaction between the metal (III) and (II) ions with three various ligands in molar ratio at aqueous ethyl alchol for (1:1:1:1) (M: O-PDA: OA: 8-HQ) [where M = Cr+3, Mn+2, Co+2, Ni+2. Cu+2 and Zn+2; O-PDA = O-Phenylenediamine; OA = Oxalic acid and 8-HQ = 8-Hydroxyquinoline]. Resulted in the formation of six – coordinate octahedral geometry was suggested for metal complexes (1-6). The ligands and complexes were tested for antibacterial and antifungal activity against Staphylococcus aureus, Staphylococcus epidermidis, Steptococcus sp., Escherichia coli, Klebsiella sp., Psedomonas aeruginosa and Candida albicans by the agar well diffusion method. Mostly, the results shown a significant increase in antibacterial and antifungal activity of the metal complexes (1-6) compared to ligands.
