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1.
《Journal of Coordination Chemistry》2012,65(2):227-242
Four new substituted amino acid ligands, N-(3-hydroxybenzyl)-glycine acid (HL1), N-(3-hydroxybenzyl)-alanine acid (HL2), N-(3-hydroxybenzyl)-phenylalanine acid (HL3), and N-(3-hydroxybenzyl)-leucine acid (HL4), were synthesized and characterized on the basis of 1H NMR, IR, ESI-MS, and elemental analyses. The crystal structures of their copper(II) complexes [Cu(L1)2]·2H2O (1), [Cu(L2)2(H2O)] (2), [Cu(L3)2(CH3OH)] (3), and [Cu(L4)2(H2O)]·H2O (4) were determined by X-ray diffraction analysis. The ligands coordinate with copper(II) through secondary amine and carboxylate in all complexes. In 2, 3, and 4, additional water or methanol coordinates, completing a distorted tetragonal pyramidal coordination geometry around copper. Fluorescence titration spectra, electronic absorption titration spectra, and EB displacement indicate that all the complexes bind to CT-DNA. Intrinsic binding constants of the copper(II) complexes with CT-DNA are 1.32?×?106?M?1, 4.32?×?105?M?1, 5.00?×?105?M?1, and 5.70?×?104?M?1 for 1, 2, 3, and 4, respectively. Antioxidant activities of the compounds have been investigated by spectrophotometric measurements. The results show that the Cu(II) complexes have similar superoxide dismutase activity to that of native Cu, Zn-SOD. 相似文献
2.
《Journal of Coordination Chemistry》2012,65(17):1513-1523
Three new copper(II) complexes with isonicotinic acid N-oxide (HL) and 1,10-phenanthroline (phen) as ligands, [Cu(L)(phen)(H2O)]2(NO3)2···2H2O (1), [Cu(L)(phen)(H2O)]2(ClO4)2···2H2O (2), and [Cu(L)(phen)Br]2- [Cu(L)(phen)(H2O)]2Br2···6H2O (3) have been synthesized and structurally characterized. The structures of all three complexes feature a Cu2 dimer formed by two Cu(II) ions interconnected by two bridging ligands. Each copper(II) ion has a distorted square pyramidal coordination geometry with elongated axial coordination by an aqua ligand or halogen anion. The isonicotinic acid N-oxide anion is bidentate, being coordinated to two Cu(II) ions through its N-O oxygen and one of its carboxylate oxygen atoms. Magnetic susceptibility measurements show a Curie–Weiss paramagnetic behavior characteristic of one unpaired electron for a copper(II) ion for all three complexes. 相似文献
3.
An aminonaphthoquinone ligand, L, and its metal complexes of general formula [MLCl2] {M = Co(II), Ni(II), Cu(II) and Zn(II)} have been synthesized and characterized by analytical and spectral techniques. Tetrahedral geometry has been assigned to Ni(II) and Zn(II) complexes and square planar geometry to Co(II) and Cu(II) complexes on the basis of electronic spectral and magnetic susceptibility data. The binding of complexes with bovine serum albumin (BSA) is relatively stronger than that of free ligand and alters the conformation of the protein molecule. Interaction of these complexes with CT-DNA has been investigated using UV-Vis and fluorescence quenching experiments, which show that the complexes bind strongly to DNA through intercalative mode of binding (Kapp 105 M?1). Molecular docking studies reiterate the mode of binding of these compounds with DNA, proposed by spectral studies. The ligand and its complexes cleave plasmid DNA pUC18 to nicked (Form II) and linear (Form III) forms in the presence of H2O2 oxidant. The in vitro cytotoxicity screening shows that Cu(II) complex is more potent against MCF-7 cells and Zn(II) complex exhibits marked cytotoxicity against A-549 cells equal to that of cisplatin. Cell imaging studies suggested apoptosis mode of cell death in these two chosen cell lines. 相似文献
4.
Zeinab Abbasi Maciej Kubicki Ali Khaleghian 《Journal of Coordination Chemistry》2017,70(12):2074-2093
Four novel Schiff base ligands and their copper(II) complexes, [Cu(L1)2] (1), [Cu(L2)2] (2), [Cu(L3)2] (3), and [Cu(L4)2] (4), were synthesized and characterized by elemental analyses, FT-IR, and UV–Vis spectroscopy. The ligands were synthesized from the condensation of 2-methoxyethylamine with various salicylaldehyde derivatives (x-salicylaldehyde for HLn, x = H (n = 1), 5-Br (n = 2), 3-OMe (n = 3), and 4-OMe (n = 4)). The molecular structures of 1, 2, and 3 were determined by the single crystal X-ray diffraction technique. The redox behavior studies of the complexes in acetonitrile display the electronic effects of the groups on the redox potential. The antioxidant activity of the Schiff base ligands and their Cu(II) complexes was evaluated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method and FRAP assay. Furthermore, the in vitro anticancer activity of compounds was screened, including MTT and migration assays against gastric cancer cell line (MKN-45). The results show that all ligands and complexes have antioxidant and anticancer activity in a concentration-dependent way. 相似文献
5.
Three ternary copper(II) complexes [Cu(L1)(phen)] (1), [Cu(L2)(phen)] (2), and [Cu(L3)(phen)]·2H2O (3) (L1 = 4-fluoro-2-(picolinamido)benzoic acid, L2 = 4,5-difluoro-2-(picolinamido)benzoic acid, L3 = 4,5-difluoro-2-((2-hydroxybenzylidene)amino)benzoic acid, phen = 1,10-phenanthroline) have been synthesized and characterized by physicochemical and spectroscopic methods. In addition, X-ray crystallography showed that the Cu atoms in each of the complexes are five-coordinate, adopting distorted square pyramidal or trigonal bipyramidal geometries. The interactions of the complexes with calf-thymus DNA were investigated by UV absorption, fluorescence spectroscopy and viscosity measurements. In addition, the complexes were screened for in vitro cytotoxicity against A549 (human pulmonary carcinoma cells), Jurkat (human T lymphocyte cell line) and HepG-2 (human liver hepatocellular carcinoma cells); these experiments showed that complex 3 exhibited the most effective cytotoxicities (IC50 = 1.224–7.099 µM). Antibacterial studies revealed that complex 3 also exhibited highest activity, consistent with the DNA binding affinities. 相似文献
6.
《Journal of Coordination Chemistry》2012,65(22):4038-4054
Four mononuclear copper(II) complexes of two new carboxamide derivatives formulated as [Cu(L1)2](ClO4)2 (1a), [Cu(L1)2](NO3)2 (1b), [Cu(L2)2(H2O)2](ClO4)2 (2a), and [Cu(L2)2(H2O)](NO3)2 (2b) have been isolated in pure form from the reaction of L1 and L2 [where L1 = N-(furan-2-ylmethyl)-2-pyridinecarboxamide and L2 = N-(thiophen-2-ylmethyl)-2-pyridinecarboxamide] with copper(II) salts of perchlorate and nitrate. All the complexes were characterized by physicochemical and spectroscopic tools along with single-crystal X-ray diffraction studies. The structural analyses showed that 1 is monomeric of square planar geometry with copper(II) chelated by two L1 ligands. Complex 2 differs in coordination geometry, being octahedral and distorted square pyramidal. Two L2 ligands occupy the equatorial positions of the octahedral 2a and the basal sites of the pyramidal 2b, with water molecules that complete the coordination sphere in each case. Electrochemical studies using cyclic voltammetry showed a reversible redox behavior of the copper(II) in 1 and 2. The electronic spectroscopic behavior and the trend of one electron equivalent redox potential corresponding to a CuII/CuI couple have also been confirmed by density functional theory calculations. The spectroscopic and viscosity measurement study in tris–HCl buffer suggested an intercalative interaction of 1a and 2 with calf thymus DNA likely due to the stacking between the non-coordinated furan and thiophene chromophore with the base pairs of DNA. 相似文献
7.
Xiongwei Dong Yuguang Li Zuowen Li Dan Gong Hai-Liang Zhu 《Transition Metal Chemistry》2011,36(3):319-324
Three new mononuclear Cu(II) and Co(III) complexes [Cu(L)Cl]ClO4 (1), [Cu(L)Cl(SCN)] (2), and [Co(L)(N3)3] (3), where L is a reduced Schiff-base ligand bi(2-fluorobenzylaminoethyl)amine, were synthesized and characterized. X-ray crystallographical
analysis reveals that the Cu(II) atom adopts a square-planar environment in complex 1, while the geometry in 2 can be described as distorted square-pyramidal. The Co(III) atom in 3 is in a distorted octahedral geometry. Three complexes were investigated for their inhibitory activities in vitro against
jack bean urease. The Cu(II) complexes 1 and 2 were found to have excellent inhibitory activities. The Co(III) complex 3 was also shown to have activity comparable to that of acetohydroxamic acid. 相似文献
8.
Jatinder Kaur Madhura Damle Hemant Mande Prasanna Ghalsasi Rajendra Kondedeshmukh 《Journal of Coordination Chemistry》2017,70(10):1667-1682
Four Ru(II) complexes with tridentate ligands viz. (4-hydroxy-N′-(pyridin-2-yl-ethylene) benzohydrazide [Ru(L1)(PPh3)2(Cl)] (1), N′-(pyridin-2-yl-methylene) nicotinohydrazide [Ru(L2)(PPh3)2(Cl)] (2), N′-(1H-imidazol-2-yl-methylene)-4-hydroxybenzohydrazide [Ru(L3)(PPh3)2(Cl)] (3), and N′-(1H-imidazol-2-yl-methylene) nicotinohydrazide [Ru(L4)(PPh3)2(Cl)] (4) have been synthesized and characterized. The methoxy-derivative of L3H (abbreviated as L3H*) exists in E configuration with torsional angle of 179.4° around C7-N8-N9-C10 linkage. Single crystal structures of acetonitrile coordinated ruthenium complexes of 1 and 3 having compositins as [Ru(L1)(PPh3)2(CH3CN)]Cl (1a) and [Ru(L3)(PPh3)2(CH3CN)]Cl (3a) revealed coordination of tridentate ligands with significantly distorted octahedral geometry constructed by imine nitrogen, heterocyclic nitrogen, and enolate amide oxygen, forming a cis-planar ring with trans-placement of two PPh3 groups and a coordinated acetonitrile. Ligands (L1H-L4H) and their ruthenium complexes (1–4) are characterized by 1H, 13C, 31P NMR, and IR spectral analysis. Ru(II) complexes have reversible to quasi-reversible redox behavior having Ru(II)/Ru(III) oxidation potentials in the range of 0.40–0.71 V. The DNA binding constants determined by absorption spectral titrations with Herring Sperm DNA (HS-DNA) reveal that L4H and 1 interact more strongly than other ligands and Ru(II) complexes. Complexes 1–3 exhibit DNA cleaving activity possibly due to strong electrostatic interactions while 4 displays intercalation. 相似文献
9.
H. R. Prakash Naik H. S. Bhojya Naik D. S. Lamani T. Aravinda B. Vijaya Kumar B. Vinay Kumar 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(8):790-795
A new ligand dibenzo[h]quinolineno[1,3,7,9] tetraazacyclododecine-7,15 (14H, 16H)-dibenzene (L) and its Co(II)/Cu(II) metal complexes of type [MLX2] (Where (M = Co(II) (5), Cu(II) (6) and X = Cl) were synthesized and are well characterized by FT-IR, 1H-NMR, FAB mass elemental analysis, and electronic spectral data. The role of the cobalt/copper metals in photo-induced DNA cleavage reactions was explored by designing complex molecules having macrocyclic structure. Finally, we have shown that photocleavage of plasmid DNA is more efficiently enhanced when this macrocyclic ligand is irradiated in the presence of copper(II) than that of cobalt metal. 相似文献
10.
Huilu Wu Jin Kong Zaihui Yang Xiaoli Wang Furong Shi Yanhui Zhang Cuiping Wang 《Transition Metal Chemistry》2014,39(8):951-960
A V-shaped ligand, 1,3-bis(1-methylbenzimidazol-2-yl)-2-thiapropane (L), and its copper(II) and manganese(II) picrate complexes have been synthesized and characterized. The compositions of the complexes are [Cu(L)2](pic)2·2DMF (1) and [Mn(L)(pic)2] (2), respectively. The crystal structure of complex 1 reveals a distorted tetrahedral geometry provided by four N donors from two ligands. Complex 2 is six coordinated, with a distorted octahedral geometry. Experimental studies of the DNA-binding properties indicated that the free ligand and both complexes bind to DNA via the intercalation mode, and the order of the binding affinity is L > 1 > 2. Antioxidant tests in vitro show that the Cu(II) complex possesses significant antioxidant activity against superoxide and hydroxyl radicals, with better scavenging effects than mannitol and vitamin C. 相似文献
11.
《Journal of Coordination Chemistry》2012,65(3):358-372
Mn(II), Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) complexes of multifunctional triaminoxime have been synthesized and characterized by elemental analyses, IR, UV–Vis spectra, magnetic moments, 1H- and 13C-NMR spectra for ligand and its Ni(II) complex, mass spectra, molar conductances, thermal analyses (DTA, DTG and TG) and ESR measurements. The IR spectral data show that the ligand is bi-basic or tri-basic tetradentate towards the metals. Molar conductances in DMF indicate that the complexes are non-electrolytes. The ESR spectra of solid copper(II) complexes [(HL)(Cu)2(Cl)2] · 2H2O (2) and [(L)(Cu)3(OH)3(H2O)6] · 7H2O (6) show axial symmetry of a d x²???y 2 ground state; however, [(HL)(Co)] (4) shows an axial type with d Z 2 ground state and manganese(II) complex [(L)(Mn)3(OH)3(H2O)6] · 4H2O (10) shows an isotropic type. The biological activity of the ligand and its metal complexes are discussed. 相似文献
12.
Some mixed ligand copper(I) complexes of general formula [Cu(L)(PPh3)3]X (X = Cl (1), ClO4 (2), BF4 (3) or PF6 (4); L = 2-(benzen-1-yl)methyleneamino-3-aminomaleonitrile) were prepared and characterized by physicochemical and spectroscopic methods. A single-crystal X-ray diffraction study of [Cu(L)(PPh3)3]CIO4 (2) revealed that the copper atom is four coordinated in a distorted tetrahedral geometry. Electrochemical studies of complexes 1–4 show quasireversible redox behavior corresponding to the Cu(I)/Cu(II) couple. Room temperature luminescence is observed for all four complexes. These complexes proved to be effective catalysts for the Sonogashira coupling of terminal alkynes with aryl halides at 90 °C. 相似文献
13.
《Journal of Coordination Chemistry》2012,65(20):3619-3628
A bidentate iminophenol (HL = 2-((4-methoxyphenylimino)methyl)-4,6-di-tert-butylphenol derived from condensation of 4-methoxyaniline and 3,5-di-tert-butyl-2-hydroxybenzaldehyde) was mixed with divalent metal salts to form the corresponding mononuclear metal complexes [MII(L)2] (M = Co (1), Cu (2), and Zn (3)). The complexes are characterized by different spectroscopic and analytical tools. X-ray crystal structures of the complexes revealed homoleptic mononuclear complexes with MN2O2 coordination. The cobalt(II) (1) and zinc(II) (3) complexes display a pseudo-tetrahedral coordination geometry, whereas the copper(II) complex (2) exhibits a distorted square-planar coordination. The zinc(II) complex (3) emits at 460 nm with a twofold enhancement of emission with respect to the free iminophenol. 相似文献
14.
《Journal of Coordination Chemistry》2012,65(23):4131-4143
Two copper(II) complexes, [Cu2(μ-benzoato)(L1)2]NO3·2H2O (1) and [Cu2(μ-succinato)(L2)2(H2O)]ClO4 (2), have been synthesized, where L1 = N′-[(E)-phenyl(pyridin-2-yl)methylidene]benzoylhydrazone and L2 = N′-[(E)-pyridin-2-ylmethylidene]benzoylhydrazone. These complexes were characterized including by single-crystal X-ray diffraction studies. The copper is five-coordinate in 1 while in 2 one copper is five-coordinate and the other is six-coordinate. Electrochemical behavior of these complexes was measured by cyclic voltammetry. The conproportionation equilibrium constants (Kcon) for both complexes have been estimated. The superoxide dismutase (SOD) activities of 1 and 2 were measured by nitro blue tetrazolium assay. Complex 1 has better SOD activity than 2. 相似文献
15.
《Journal of Coordination Chemistry》2012,65(22):4055-4069
Two new N2O2 unsymmetrical Schiff bases, H2L1 = 3-[({o-[(E)-(o-hydroxyphenyl)methylideneamino]phenyl}methyl)imino]-1-phenyl-1-buten-1-ol and H2L2 = 3-[({o-[(E)-(2-hydroxy-1-naphthyl)methylideneamino]phenyl}methyl)imino]-1-phenyl-1-buten-1-ol, and their copper(II) and nickel(II) complexes, [CuL1] (1), [CuL2] (2), [NiL1] (3), and [NiL2] (4), have been synthesized and characterized by elemental analyses and spectroscopic methods. The crystal structures of these complexes have been determined by X-ray diffraction. The coordination geometry around Cu(II) and Ni(II) centers is described as distorted square planar in all complexes with the CuN2O2 coordination more distorted than the Ni ones. The electrochemical studies of these complexes indicate a good correlation between the structural distortion and the redox potentials of the metal centers. The ligand and metal complexes were also screened for their in vitro antibacterial activity. 相似文献
16.
《Journal of Coordination Chemistry》2012,65(11):1775-1783
Two copper(II) complexes of disubstituted 2,2′-bipyridine (bpy = 2, 2′-bipyridine) with tetraalkylammonium groups, [Cu(L1)2Br](ClO4)5·2H2O (1) and [Cu(L2)2Br](ClO4)5·H2O (2) (L1 = [4, 4′-(Et3NCH2)2-bpy]2+, L2 = [4, 4′-((n-Bu)3NCH2)2-bpy]2+), have been synthesized and characterized. X-ray crystallographic study of 1 indicates that Cu(II) is a distorted trigonal bipyramidal or square pyramid. DNA binding of both complexes was studied by UV spectroscopic titration. In the presence of reducing reagents, the cleavage of plasmid pBR322 DNA mediated by both complexes was investigated and efficient oxidative cleavage of DNA was observed. Mechanistic study with reactive oxygen scavengers indicates that hydrogen peroxide and singlet oxygen participate in DNA cleavage. 相似文献
17.
《Journal of Coordination Chemistry》2012,65(24):4296-4313
A series of albendazole-based copper(II) complexes with different counter anions, [Cu(Albz)(H2O)2](ClO4)2 (1), [Cu(Albz)2(Cl)]Cl·2H2O (2), [Cu(Albz)2(NO3)](NO3) (3), and [Cu2(Albz)2(μ-SO4)2(H2O)2] (4) (Albz = albendazole), have been synthesized and characterized. Their structures and properties were characterized by elemental analysis, thermal analysis (TGA, DTG and DTA), IR, UV–vis and ESR spectroscopies, cyclic voltammetry, electrical molar conductivity, and magnetic moment measurements. A square-planar geometry is proposed for 1, whereas the five-coordinate copper(II) complexes 2, 3, and 4 have a square pyramidal geometry. Theoretical calculations (DFT) using B3LYP/6–311 + G(d,p) level of theory corroborated the experimental results to investigate both the drug Albz and its copper(II) complex, 1. The hepatoprotective and antioxidative efficacy of Albz and 1–4 were evaluated against carbon tetrachloride-induced acute hepatotoxicity in rats. Hepatotoxicity in experimental rats was evidenced by significant decrease in the antioxidant enzyme activities (SOD, GSH-S-transfers, and GSH-Rd levels). The results have strong impact for designing anticancer drugs, combined with their potential cytotoxic and antioxidant activities, which can be targeted selectively against cancer cells and increase their therapeutic index and advantages over other anticancer drugs. The DNA cleavage studies of Albz and its copper(II) complexes using genomic DNA indicated that Albz has no role in cleavage of DNA, and only 1 played a marked role in the DNA cleavage without any external additives. 相似文献
18.
Few novel mixed ligand copper(II) complexes of the type [Cu(L)(Cl)2(H2O)], [Cu(L)2]Cl2, [Cu(L)L1] and [Cu(L)(phen)H2O]Cl2 (where L is the ligand obtained from the condensation of N-(2-aminoethyl)-1,3-propanediamine with m-nitrobenzaldehyde (La)/o-chlorobenzaldehyde (Lb)/benzaldehyde (Lc)/p-methoxybenzaldehyde (Ld)/p-hydroxybenzaldehyde (Le)/furfuraldehyde (Lf)/pyrrole-2-carboxaldehyde (Lg); L1 is another ligand obtained from the condensation of anthranilic acid with salicyaldehyde; phen = 1,10-phenanthroline) have
been synthesized and characterized by the spectral and analytical techniques. From these data, it is found that the ligands
adopt distorted octahedral geometry on metalation with Cu(II) ion. The XRD data indicate that the complexes are polycrystalline
with nanosized grains. The SEM images of [Cu(La)phen(H2O)]Cl2 and [Cu(Lf)2]Cl2 complexes show that they have leaf and cauliflower like morphology. The in vitro biological screening effects of the investigated
compounds have been tested against the bacteria such as Escherichia coli, Klebsiella pneumoniae, Salmonella typhi, Pseudomonas aeruginosa and Staphylococcus aureus and fungi such as Aspergillus niger, Rhizopus stolonifer, Aspergillus flavus, Rhizoctonia bataicola and Candida albicans by the well diffusion method. A comparative study of MIC values of the Schiff base ligands and their complexes indicates
that the complexes exhibit higher antimicrobial activity than the free ligands. An electrochemical study of the copper complexes
containing electron withdrawing substituted ligands reveals that they prefer to bind to DNA in Cu(II) rather than Cu(I) oxidation
state. 相似文献
19.
《Journal of Coordination Chemistry》2012,65(4):632-649
Two mixed-ligand complexes, [Cu(L)(2imi)] (1) and [Ni(L)(2imi)]·MeOH (2) [L = 2-(((5-chloro-2-oxyphenyl)imino)methyl)phenolato) and 2imi = 2-methyl imidazole], have been prepared by the reaction of appropriate metal salts with H2L and 2-methyl imidazole. Their structures were characterized by microanalysis, FT-IR, UV–vis, molar conductivity, and 1H NMR for [Ni(L)(2imi)]·MeOH. The structures were determined using single crystal X-ray diffraction. Each four-coordinate metal center, Cu(II) in 1 and Ni(II) in 2, is surrounded by donors of Schiff base (L2?) and N of 2-methyl imidazole in square planar geometries. α-Amylase activities of these compounds have also been investigated. The experimental data showed that α-amylase was inhibited by Ni(II) complex while the Cu(II) complex causes a 1.3-fold decrease in Km value. Antimicrobial results show that these compounds, especially the Cu(II) complex, have potential for antibacterial activity against Gram negative and Gram positive bacteria and antifungal activity against Aspergillus fumigatus. 相似文献
20.
Sihan Guo Tianrui Wang Jiajin Xin Qiqige Hu Shanfa Ren Guihua Sheng 《Journal of Coordination Chemistry》2017,70(20):3449-3458
Two new copper(II) complexes, [CuL(HL)]·ClO4 (1) and [Cu2Br2L2]·0.85H2O (2), where L is the monoanionic form of 4-tert-butyl-N′-(1-(pyridin-2-yl)ethylidene)benzohydrazide (HL), have been prepared. The complexes were characterized by infrared and UV–vis spectra, and single crystal X-ray diffraction. Complex 1 is a mononuclear copper(II) species and 2 is a bromido-bridged dinuclear copper(II) species. The Cu ion in 1 is in an octahedral coordination mode and that in 2 is trigonal-bipyramidal. The Jack bean urease inhibitory assay indicated that 2 is active, with IC50 value of 20.6 ± 2.3 μmol L?1, while 1 is inactive. Molecular docking of 2 with Jack bean urease was studied. 相似文献