title: Structural studies and anticancer activity of a novel (N6O4) macrocyclic ligand and its Cu(II) complexes.
abstract: A novel (N6O4) macrocyclic ligand (L) and its Cu(II) complexes have been prepared and characterized by elemental analysis, spectral, thermal (TG/DTG), magnetic, and conductivity measurements. Quantum chemical calculations have also been carried out at B3LYP/6-31+G(d,p) to study the structure of the ligand and one of its complexes. The results show a novel macrocyclic ligand with potential amide oxygen atom, amide and amine nitrogen atoms available for coordination. Distorted square pyramidal ([Cu(L)Cl]Cl·2.5H2O (1), [Cu(L)NO3]NO(3)·3.5H2O (2), and [Cu(L)Br]Br·3H2O (4) and octahedral ([Cu(L)(OAc)2]·5H2O (3)) geometries were proposed. The EPR data of 1, 2, and 4 indicate d1x2(-y)2 ground state of Cu(II) ion with a considerable exchange interaction. The measured cytotoxicity for L and its complexes (1, 2) against three tumor cell lines showed that coordination improves the antitumor activity of the ligand; IC50 for breast cancer cells are ≈8.5, 3, and 4 μg/mL for L and complexes (1) and (2), respectively.
authors.affiliation: Department of Chemistry, Faculty of Science, El-Menoufia University, Shebin El-Kom, Egypt.
authors.forename: Hanaa A
authors.initials: HA
authors.lastname: El-Boraey
authors.forename: Sanaa M
authors.initials: SM
authors.lastname: Emam
authors.forename: Dina A
authors.initials: DA
authors.lastname: Tolan
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: El-Nahas
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry* / Q000494:pharmacology*; D045744:Cell Line, Tumor; D003300:Copper / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D004583:Electrons; D006801:Humans; D008024:Ligands; D047028:Macrocyclic Compounds / Q000737:chemistry* / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D008280:Magnetics; D013058:Mass Spectrometry; D008956:Models, Chemical; D013055:Spectrophotometry, Infrared; D013696:Temperature; D013818:Thermogravimetry; D014732:Vibration
chemical_list: D000970:Antineoplastic Agents; D008024:Ligands; D047028:Macrocyclic Compounds; D003300:Copper