Synthesis, Structural Characterization and Biological Activity of Novel Cyclohexane-1,3-dione Ligands and Their Metal Complexes

Some new Zn(II) and Cu(II) complexes [Cu(L1)(OAc)2]∙H2O, [Cu(L1)(NO3)H2O]∙NO3∙3.5H2O, [Zn(L1)(NO3)2]∙4.5H2O, [Zn(L1)(OAc)2(H2O)2]∙3H2O, [Cu2(L2)(OAc)4]∙2H2O∙2DMF, [Cu(L2)2]∙2NO3∙1.5DMF∙H2O, [Zn(L2)2(NO3)2]∙DMF and [Zn2(L2)(OAc)4(H2O)4]∙5H2O; L1 = 2-[2-(2-methoxyphenyl)hydrazono]cyclohexane-1,3-dione and L2 = 2-[2-(3-nitrophenyl)hydrazono]cyclohexane-1,3-dione were synthesized and characterized by IR, 1H-NMR,13C-NMR and ultraviolet (UV-Vis.) spectroscopy, elemental analysis, magnetic susceptibility, mass spectrometry and thermogravimetry-differential thermal analysis (TGA-DTA). The synthesized ligands and their complexes were tested for antibacterial activity against Escherichia coli ATCC 25922, Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 25923, and Salmonella typhimurium CCM 583. Some of complexes showed medium-level antibacterial activity against the test bacteria compared with ampicillin.