title: Synthesis, spectral characterization, molecular modeling, thermal study and biological evaluation of transition metal complexes of a bidentate Schiff base ligand.
abstract: Complexes of copper(II) and nickel(II) of general composition M(L)2X2, have been synthesized [where L=3-Bromoacetophenone thiosemicarbazone and X=CH3COO(-), Cl(-) and NO3(-)]. All the complexes were characterized by elemental analysis, magnetic moments, IR, electronic and EPR spectral studies. The ligand behaved as bidentate and coordinated through sulfur of -C=S group and nitrogen atoms of -C=N group. The copper(II) and nickel(II) complexes were found to have magnetic moments 1.94-2.02 BM, 2.96-3.02 BM respectively which was corresponding to one and two unpaired electrons respectively. The molar conductance of the complexes in solution of DMSO lies in the range of 10-20 Ω(-1) cm(2) mol(-1) indicating their non-electrolytic behavior. On the basis of EPR, electronic and infrared spectral studies, tetragonal geometry has been assigned for copper(II) complexes and an octahedral geometry for nickel(II) complexes. The values of Nephelauxetic parameter β lie in the range 0.19-0.37 which indicated the covalent character in metal ligand 'σ' bond. Synthesized ligand and its copper(II) and nickel(II) complexes have also been screened against different bacterial and fungal species which suggested that complexes are more active than the ligands in antimicrobial activities.
authors.affiliation: Department of Chemistry, Zakir Husain Delhi College (Delhi University), JLN Marg, New Delhi 110 002, India. schandra_00@yahoo.com
authors.forename: Sulekh
authors.initials: S
authors.lastname: Chandra
authors.forename: Savita
authors.initials: S
authors.lastname: Bargujar
authors.forename: Rita
authors.initials: R
authors.lastname: Nirwal
authors.forename: Kushal
authors.initials: K
authors.lastname: Qanungo
authors.forename: Saroj K
authors.initials: SK
authors.lastname: Sharma
mesh_terms: D000838:Anions; D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D000935:Antifungal Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D056831:Coordination Complexes / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D004578:Electron Spin Resonance Spectroscopy; D004583:Electrons; D005658:Fungi / Q000187:drug effects; D008024:Ligands; D060328:Magnetic Phenomena; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008958:Models, Molecular; D012545:Schiff Bases / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D013055:Spectrophotometry, Infrared; D013696:Temperature; D028561:Transition Elements / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000838:Anions; D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D056831:Coordination Complexes; D008024:Ligands; D012545:Schiff Bases; D028561:Transition Elements
keywords: Antibacterial activity; Antifungal activities; Copper(II) and nickel(II) complexes; In vitro screening; Thiosemicarbazone