title: Mixed ligand complexes of Cu(II)-2-(2-pyridyl)-benzimidazole and aliphatic or aromatic dicarboxylic acids: Synthesis, characterization and biological activity.
abstract: The synthesis and structural characterization of mixed ligand complexes derived from 2-(2-pyridyl)-benzimidazole (PBI) (1ry ligand) and aliphatic or aromatic dicarboxylic acids (2ry ligand) are reported. Cu(II) complexes were characterized on the bases of their elemental analyses, IR, ESR and thermal analyses. The elemental analysis indicated the formation of mixed ligand complexes in a mole ratio 1:1:1 (Cu:L(1):L(2)), L(1)=PBI and L(2)=oxalic acid, phthalic acid or malonic acid. IR spectra showed that PBI acts as a neutral bidentate coordinated to the Cu(II) via the pyridyl and imidazolyl nitrogen atoms. The dicarboxylic acids are bidentate with monodentate carboxylate groups. Thermal decomposition study of complexes was monitored by thermogravimetric (TG) and derivative thermogravimetric (DTG) analysis in N(2) atmosphere. The decomposition course and steps were analysed and the activation parameters of the nonisothermal decomposition were calculated from the TG curves and discussed. The isolated metal chelates were screened for their antimicrobial activities and the results are reported, discussed and compared with some known antibiotics.
authors.affiliation: Department of Chemistry, Faculty of Science, Cairo University, Cairo, Egypt. aelsherif72@yahoo.com
authors.forename: Ahmed A
authors.initials: AA
authors.lastname: El-Sherif
authors.forename: Bakir J A
authors.initials: BJ
authors.lastname: Jeragh
mesh_terms: D001419:Bacteria / Q000187:drug effects; D001562:Benzimidazoles / Q000138:chemical synthesis* / Q000737:chemistry* / Q000494:pharmacology; D003998:Dicarboxylic Acids / Q000138:chemical synthesis* / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D007700:Kinetics; D008024:Ligands; D008826:Microbial Sensitivity Tests; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry* / Q000494:pharmacology; D013055:Spectrophotometry, Infrared; D013696:Temperature; D013818:Thermogravimetry
chemical_list: D001562:Benzimidazoles; C526669:Cu(II)-2-(2-pyridyl)-benzimidazole; D003998:Dicarboxylic Acids; D008024:Ligands; D009942:Organometallic Compounds; C031000:benzimidazole