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1.
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.
The complexes [Zn(phenylacetato)2(2-aminopyridin)2] (3), [Zn(phenylacetato)2(1,10-phenanthroline)]·H2O (4), and [Zn(phenylacetato)2(2,9-dimethyl-1,10-phenanthroline)]·0.5 H2O (5) were prepared and characterized by IR-, UV–Visible, 1H and 13C NMR spectroscopy, and single crystal X-ray diffraction. BNPP hydrolysis of the complexes and their parent nitrogen ligands showed that the hydrolysis rate of bis-(4-nitrophenyl) phosphate (BNPP) was 1.7 × 105 L mol?1 s?1 for 3, 3.1 × 105 L mol?1 s?1 for 4 and 4.3 × 104 L mol?1 s?1 for 5. Antibacterial activities show the effect of complexation on activity against Gram-positive (S. epidermidis, S. aureus, E. faecalis, M. luteus and B. subtilis) and Gram-negative (K. pneumonia, E. coli, P. mirabilis and P. aeruginosa) bacteria using the agar well diffusion method. Complex 4 showed good activity against G? bacteria except P. aeruginosa, and against G+ bacteria except E. ferabis. Complex 5 showed no activity against G? bacteria, low activity against M. luteus and B. subtilis bacteria and high activity against S. epidemidis and S. aureus. Complex 3 did not show any activity against G? or G+ bacteria.  相似文献   

3.
Assembly of orotic acid (H3Or, 1,2,3,6-tetrahydro-2,6-dioxo-4-pyrimidinecarboxylic) and Cd(NO3)·6H2O yielded a coordination polymer, [(Cd(Hor)·2.5H2O)2]n (1), which has been characterized by X-ray single-crystal diffraction, TGA, and ?uorescence spectra. Single-crystal X-ray structural analyses reveal that 1 is a hydrogen-bonded binuclear Cd-orotate coordination polymer in which both Cd2+ ions have different coordination environments with identical distorted octahedral geometry. Crystal data for 1: monoclinic, space group P21/n, a = 7.0209(10) Å, b = 13.974(2) Å, c = 17.541(3) Å, β = 98.842(2)°, V = 1700.5(4) Å, Z = 4, R1 = 0.0269, wR2 = 0.0612, θmax = 25.960. The emission spectrum of the Cd-complex recorded with 265 nm excitation wavelength reveals the complex has strong blue luminescence with the peak maximum 420 nm (2.95 eV) as a result of the nπ* and ππ* transitions on the H3Or ligand.  相似文献   

4.
Seven new transition metal complexes formulated as [M2(1,4-tpbd)(diimine)2(H2O)2]4+ [M = Zn, Co, Ni, Cd; 1,4-tpbd = N,N,N′,N′-tetrakis(2-pyridylmethyl)benzene-1,4-diamine; diimine is a N,N-donor heterocyclic base like 1,10-phenanthroline (phen), 2,2′-bipyridine (bpy), 4,5-diazafluoren-9-one (dafo)] have been synthesized and structurally characterized by X-ray crystallography: [Zn2(1,4-tpbd)(phen)2(H2O)2]4+ (1), [Zn2(1,4-tpbd)(bpy)2(H2O)2]4+ (2), [Co2(1,4-tpbd)(phen)2(H2O)2]4+ (3), [Ni2(1,4-tpbd)(phen)2(H2O)2]4+ (4), [Ni2(1,4-tpbd)(bpy)2(H2O)2]4+ (5), [Ni2(1,4-tpbd)(dafo)2(H2O)2]4+ (6) and [Cd2(1,4-tpbd)(phen)2(H2O)2]4+ (7). Single crystal diffraction reveals that the metals in the complexes are all in a distorted octahedral geometry. The interactions of the seven complexes with calf thymus DNA (CT-DNA) have been investigated by UV absorption, fluorescence, circular dichroism spectroscopy and viscosity measurements. The apparent binding constants (Kapp) are calculated to be 5.2?×?105 M?1 for 1, 1.05?×?105 M?1 for 2, 5.76?×?105 M?1 for 3, 4.57?×?105 M?1 for 4, 1.29?×?105 M?1 for 5, 1.7?×?105 M?1 for 6, 2.53?×?105 M?1 for 7, the binding propensity to the calf thymus DNA in the order: 3 (Co-phen) > 1 (Zn-phen) > 4 (Ni-phen) > 7 (Cd-phen) > 6 (Ni-dafo) > 5 (Ni-bpy) > 2 (Zn-bpy). Furthermore, these complexes display efficient oxidative cleavage of supercoiled DNA; the Zn(II)/H2O2 and Cd(II)/H2O2 systems efficiently cleave DNA attributed to the peroxide ion coordinated to the Zn(II) and Cd(II), which enhanced their nucleophilicity, this is rare.  相似文献   

5.
Hydrothermal reactions of Sm2O3, Gd(ClO4)3?·?6H2O and Tb(ClO4)3?·?6H2O with nitrilotriacetic acid, give rise to three lanthanide coordination polymers, {[Sm(NTA)(H2O)2]?·?H2O} n (1), {[Gd(NTA)(H2O)]?·?H2O} n (2) and {[Tb(NTA)(H2O)]?·?H2O} n (3). Their solid-state structures have been characterized by elemental analysis, and IR spectroscopy. X-ray single-crystal diffraction analyses indicated that 2 and 3 are isomorphous three-dimensional coordination polymers with eight-coordinate Gd(III) (or Tb(III)), while 1 forms a two-dimensional coordination polymer containing nine-coordinate Sm(III). The photophysical properties of 3 have been studied with excitation and emission spectra, which exhibit strong green emission.  相似文献   

6.
Two tetranuclear manganese complexes, [Mn4(L1)6](ClO4)2?2.75H2O (1) [HL1 = 4-methyl-2-((pyridin-2-ylmethylene)amino)phenol] and [Mn4(L2)4(NO3)3(OH)]?pz?3H2O (2) [HL2 = (1H-pyrazol-1-yl)(pyridin-2-yl)methanol, pz = pyrazole], have been synthesized and characterized by IR spectroscopy, elemental analysis, single-crystal X-ray diffraction, and magnetic measurements. The structural analysis revealed that the central manganese ion is linked with three apical manganese ions through six phenoxo-bridges creating a Mn4O6 core for 1; 2 has a cubane-like topology with the Mn(II) ions and the deprotonated oxygens from L2 alternatively occupying vertices. The magnetic studies indicated a weak ferromagnetic coupling interaction (J = 0.48 ± 0.087 cm?1, g = 2.00, θ = ?0.78 K) for 1 and a weak antiferromagnetic spin-exchange interaction (J1 = ?0.50 ± 0.075 cm?1, J2 = ?0.13 ± 0.082 cm?1, g = 1.98) between Mn(II) ions for 2. The magnetostructural correlations of the two Mn4 clusters have been discussed tentatively.  相似文献   

7.
Two new compounds, [Cd2(bptc)(bpimb)(H2O)]?·?2H2O (1) and [Cd2(bptc)(bpib)]?·?4H2O (2) (where H4bptc?=?biphenyl-3,3′,4,4′-tetracarboxylic acid, bpimb?=?1,3-bis((2-(pyridin-2-yl)-1H-imidazol-1-yl)methyl)benzene, bpib?=?1,4-bis(2-(pyridin-2-yl)-1H-imidazol-1-yl)butane), were synthesized by reactions of the corresponding metal salts with H4bptc and N-containing auxiliary ligands and their structures have been determined by single-crystal X-ray diffraction. Compound 1 is built by Cd4-clusters which further construct a 3-D (3,8)-connected framework with tfz-d notation; 2, also built by Cd4-clusters, is a 3-D (4,8)-connected framework with (32?·?42?·?52)(34?·?48?·?512?·?64) topology. In addition, the elemental analyses, infrared spectra, fluorescence, and thermogravimetric analyses for 1 and 2 are discussed.  相似文献   

8.
[CoIII(L1)2·H2O]NO3 (1), [MnII(L1)2·H2O] (2), and [ZnII(L1)2·H2O] (3) with a hydrazone derived from protocatechuic acid (HL1 = C15H13N3O3) were designed, synthesized, and characterized by C, H, N elemental analyses, single-crystal X-ray diffraction, and IR spectra, which revealed that the three complexes are similar structures. Docking study has been done. The urease inhibitory activities of the three complexes were tested. Complexes 1 and 3 showed strong inhibitory activity against jack bean urease with IC50 values of 45.9 and 11.64 μM. Complex 2 had no obvious inhibitory activity to urease; the IC50 was > 50 μM.  相似文献   

9.
Two new complexes, [Mn(H2bptc)(2,2′-bpy)2]?·?2H2O (1) and [Mn3(Hbptc)2(2,2′-bpy)3(H2O)8]?·?2H2O (2) (H4bptc?=?biphenyl-2,5,2′,5′-tetracarboxylic acid, 2,2′-bpy?=?2,2′-bipyridine), have been synthesized under hydrothermal conditions. Their structures have been characterized by single-crystal X-ray diffraction, elemental analyses, IR spectra, powder X-ray diffraction, and thermogravimetric analyses. Complexes 1 and 2 are both linked into 3-D supramolecular networks by non-covalent interactions (O–H?···?O, C–H?···?O, C–H?···?π, and π?···?π). Complexes 1 and 2 exhibit weak antiferromagnetic interactions.  相似文献   

10.
Mononuclear [Ce(pztza)2(H2O)6](pztza)·H2O (1) (pztza = 5-(2-pyrazinyl)tetrazole-2-acetato) has been prepared and characterized by IR, elemental analysis and single-crystal X-ray diffraction. PEG-5000 (poly(ethyleneglycol-5000)) coated [Ce(pztza)2(H2O)6](pztza)·H2O nanoparticles (NPs) can disperse into distilled water. In vitro study on Hela cells shows that Hpztza is nontoxic while [Ce(pztza)2(H2O)6](pztza)·H2O NPs show high toxicity with half-maximal inhibitory concentration (IC50) of 17 μg/mL (1.93 × 10?5 M). In addition, such NPs can inhibit the migration of Hela cells effectively.  相似文献   

11.
Four Cd(II)- and Cu(II)-containing coordination polymers (CPs) based on a multidentate N-donor ligand and varied dicarboxylate anions, [Cd(3,3′-tmbpt)(p-bdc)]·2.5H2O (1), [Cd(3,3′-tmbpt)(m-bdc)]·2H2O (2), [Cu(3,3′-tmbpt)(m-bdc)]·H2O (3), and [Cu(3,3′-tmbpt)(p-bdc)]·2H2O (4), where 3,3′-tmbpt = 1 ? ((1H-1,2,4-triazol-1-yl)methyl)-3,5-bis(3-pyridyl)-1,2,4-triazole, p-H2bdc = 1,4-benzenedicarboxylic acid, and m-H2bdc = 1,3-benzenedicarboxylic acid, have been prepared hydrothermally. The structures of the compounds were determined by single-crystal X-ray diffraction analyses and further characterized by infrared spectra and elemental analyses. Compound 1 exhibits a 3-D twofold interpenetrating framework with a 65·8 CdSO4 topology. Compound 2 is a 2-D layer containing meso-helical chains with a 44·62 sql topology. Compound 3 shows a 1-D → 3-D interdigitated architecture while 4 displays a 2-D → 3-D interdigitated architecture. The structural differences of the compounds indicate that the dicarboxylate anions and the central metal ions play important roles in the resulting structures of CPs. Optical band gaps and solid-state photoluminescent properties have also been studied.  相似文献   

12.
Two new hybrid compounds, [Cu(1)(phen)(H2O)][Cu(2)(phen)(H2O)]([Cu(3)]0.25(H2O)][P2Mo5O23]·3.75H2O (1) and [Cu(en)2]1.5[P2Mo5O23]2·(enH2)3·2H2O (2) (phen = 1,10-phenanthroline, en = ethylenediamine), have been hydrothermally synthesized and characterized by IR, UV–Vis spectroscopy, X-ray photoelectron spectroscopy (XPS), powder XRD analyses, TG analyses, cyclic voltammogram analyses, elemental analyses, and single crystal X-ray diffraction analyses. Single crystal X-ray diffraction analyses reveal that the two compounds have a 1-D chain structure formed by Strandberg-type POMs and TMCs with –A–B–C–B–A–B–C–B– linking mode, then further extend into a 2-D layer structure through π?π or hydrogen bond interactions.  相似文献   

13.
The rhenium(II) dinitrosyl and mononitrosyl complexes, i.e. [Re(NO)2(CN)4]·(Phen)2·2H2O (1) and PhenH[Re(NO)(CN)4(H2O)]·(Phen)·3H2O (2) have been isolated and characterized. The X-ray crystal structure of 2 reveals that Re(II) is octahedrally coordinated with one nitrosyl, four cyanides, and one water, with one phenanthroline protonated to compensate the charge of the Re(II) center. The crystal structure shows chemically significant non-covalent interactions like hydrogen bonding involving the uncoordinated water and ππ interactions between phenanthrolinium and phen. The structures of both complexes have been optimized by DFT. Absorption and emission spectral studies and viscosity measurements indicate that both 1 and 2 interact with calf thymus DNA through partial intercalation of DNA bases. The intrinsic-binding constants, obtained from UV–vis spectroscopic studies, are 1.2?×?104 and 7.2?×?104?M?1 for 1 and 2, respectively. Both 1 and 2 are capable of inducing cleavage of plasmid DNA in the presence of H2O2 to form the supercoiled form to nicked circular form. The spectroscopic results of DNA binding are supported by molecular docking studies.  相似文献   

14.
Two new complexes, [MnL2](ClO4) (1) and [CuL2] (2) (where LH = (E)-1-((3-(dimethylamino)propylimino)methyl)naphthalen-2-ol), have been synthesized and characterized by spectroscopic techniques and their molecular structures are established by single-crystal X-ray diffraction study. Complex 1 adopts an octahedral geometry around the central manganese atom which is in + 3 oxidation state, whereas in complex 2, the Cu+2 ion preferred a square pyramidal environment around it through the ligand donor atoms. Both complexes were tested for catecholase and phenoxazinone synthase activity. Complex 1 catalyzes the oxidation of 3,5-ditertiary-butyl catechol with a kcat value of 6.8424 × 102 h?1 in acetonitrile whereas the same for complex 2 is 3.7485 × 102 h?1 in methanol. Phenoxazinone synthase activity was shown only by complex 2 having kcat = 74.225 h?1. Structures of both the title complexes have been optimized by means of DFT calculations. Experimental electronic spectra of the complexes have been corroborated by TDDFT analysis. Electrochemical investigations by means of cyclic voltammetry have been carried out to study the electron transfer processes in the complexes.  相似文献   

15.
By selecting appropriate ligands, two polyoxidovanadate complexes, [Ni(en)2]3[V18O42Cl]·7H2O·2H3O+ (1) and [H2N(CH3)2]3[PV14O42]·2TMP·6H3O+ (2), have been synthesized at different pH values using V2(SO4)3, Ni(CH3COO)2, and H6TTHA (for 1), VO(acac)2 and TPP (for 2) (en = C2H8N2, TPP = thiamine pyrophosphate, TMP = thiamine monophosphate, H6TTHA = 1,3,5-triazine-2,4,6-triamine hexaacetic acid). The complexes have been characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis (TG), and single crystal X-ray diffraction. The complexes catalyze the oxidation of the organic substrate phenol red in the presence of H2O2 and bromide, and the reaction system is considered as a model for hydrogen peroxide determination. The reaction rate constants (k) for 1 and 2 are calculated as 3.729 × 103 and 4.083 × 103 (mol L)?2 s?1. The maximum conversion rate of phenol red for 1 is 83.32%, while for 2 is 81.12%.  相似文献   

16.
Reactions of copper salts, zoledronic acid, and 2,2′-bipyridine/1,10-phenanthroline in aqueous ethanolic solutions afforded four phosphonate oxygen-bridged copper complexes, Cu(bipy)(H4zdn)(HSO4) (1), [Cu2(bipy)2(H2zdn)(H2O)(Cl)]·4H2O (2), [Cu2(phen)2(H2zdn)(H2O)(Cl)]·2.5H2O (3), and [Cu3(bipy)3(H4zdn)(H2zdn)(SO4)]·5H2O (4) (H5zdn = zoledronic acid, bipy = 2,2′-bipyridine, phen = 1,10-phenanthroline). The copper centers of 14 have square pyramidal coordination geometries. The Cu(II) ions are coordinated to bipy/phen, zoledronate, and HSO4?/Cl? forming mononuclear units for 1, dinuclear for 2 and 3, and trinuclear for 4. These building units are further extended into 3-D supramolecular networks via multiple hydrogen bond interactions. Temperature-dependent magnetic properties of 2 and 4 suggest weak antiferromagnetic coupling (J = ?4.53(8) cm?1 for 2, J = ?1.69(4) cm?1 for 4). The antitumor activity of 2 was evaluated against the human lung cancer cell line and indicates effective time- and dose-dependent cytotoxic effects.  相似文献   

17.
Two binuclear oxo-bridged half-titanocene complexes, µ-oxo-bis[(1-aryl-2,3,4,5-tetramethylcyclopentadienyl)dichlorotitanium] [(ArMe4CpTiCl2)2O, Ar?=?4- i PrC6H4 (3), 4- t BuC6H4 (4)], have been prepared by the treatment of 1-aryl-2,3,4,5-tetramethylcyclopentadienyltitanium trichloride [ArMe4CpTiCl3, Ar?=?4- i PrC6H4 (1), 4- t BuC6H4 (2)] with 0.5?equiv of H2O. Complexes 3 and 4 have been characterized by elemental analysis and 1H- and 13C-NMR (nuclear magnetic resonance; NMR) spectroscopies, and their molecular structures have been determined by X-ray crystallography. When activated with i Bu3Al and Ph3CB(C6F5)4, complexes 3 and 4 both exhibit reasonable catalytic activity for ethylene polymerization (90?×?103 to 280?×?103?kg PE (mol?Ti)?1?bar?1?h?1), producing polyethylenes with moderate molecular weight.  相似文献   

18.
A new coordination polymer, [Ni(pydc)(H2O)2]?·?H2O (1) (H2pydc?=?pyridine-3,4-dicarboxylic acid), have been synthesized by treating Ni(II) nitrate with 3,4-pyridinedicarboxylic acid under hydrothermal conditions. The single-crystal X-ray structure reveals that 1 is a 2D bi-layered coordination polymer. Single-crystals are triclinic, space group P 1 , with a?=?7.065(3), b?=?7.812(4), c?=?9.031(4)?Å, α?=?75.568(8), β?=?68.970(8), γ?=?75.927(8)°, V?=?444.0(3)?Å3, Z?=?2. Variable temperature magnetic susceptibility measurements demonstrate a ferromagnetic interaction in 1.  相似文献   

19.
A new quinoline-based chemosensor 1 has been designed and synthesised. Its metal ion-binding properties have been documented in organic and aqueous organic solvents. While chemosensor 1 recognises Hg2+ ions (K a = 2.15 × 104 M? 1) by exhibiting ratiometric change in emission in CHCl3/CH3OH (1:1, v/v), under similar condition both Zn2+ and Cd2+ ions are sensed by significant non-ratiometric increase in emission with measurable red shift. In DMSO/H2O (5:95, v/v), the sensor 1 exhibits a greater selectivity towards Hg2+ ions (K a = 9.20 × 103 M? 1) over the other metal ions examined.  相似文献   

20.
Two 3-D organic–inorganic hybrid supermolecular complexes, Na(BiHEDTA·2H2O)3(PW12O40)·2H3O (BiPW) and Na(BiHEDTA·2H2O)3(PMo12O40)·2H3O·2H2O (BiPMo) ethylenediamine tetraacetic acid (EDTA) have been synthesized by solution method and characterized by ultraviolet visible (UV–vis) spectroscopy, thermogravimetric-differential thermal analysis, photoluminescence, cyclic voltammetry, and single-crystal X-ray diffraction (XRD). XRD analysis reveals that BiPW and BiPMo are isostructural with 3-D architectures assembled by 2-D layer tetranuclear cation and a Keggin-type polyoxoanion. Although these two hybrids exhibit similar structures, the properties depend on the nature of polyoxoanion [PM12O40]3? (M = W, Mo). Under UV irradiation, BiPW and BiPMo show fast response of reversible and irreversible photochromism, respectively. BiPW exhibits excellent photocatalytic activity in degradation of methyl orange dyes under irradiation of UV–visible light. It can be reused for at least six cycles without obvious loss of activity in the degradation experiments; BiPMo shows catalytic activity in elimination of methanol. The elimination rate of methanol reaches 56.9% when the concentration of methanol is 2.3 g·m?3 and the flow velocity is 10 mL·min?1 at 100 °C.  相似文献   

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