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71.
Three compounds, [(CH3)2NH2][M3(BTC)(HCOO)4(H2O)]·H2O (M = Mn (1), Co (2), Ni (3), H3BTC = 1,3,5-benzenetricarboxylic acid), were synthesized under hydrothermal conditions and were characterized by single crystal and powder X-ray diffraction, IR spectra, elemental analysis, coupled TG-MS and magnetic measurements. Compounds 1-3 are isostructural analogues and crystallize in monoclinic space group P21/c. Each metal ion in these compounds connects to six oxygen atoms to form a MO6 octahedron. Six MO6 octahedra link to each other to form a corner-shared hexameric M6 cluster, which is linked by BTC ligands to form two-dimensional layers. The two-dimensional layers are further connected by formic ions to form a three-dimensional network with channels, where (CH3)2NH2+ ions and water molecular are located. Magnetic measurements indicate that anti-ferromagnetic ordering occurs at low temperature for these compounds. 相似文献
72.
The reaction between nickel(II) nitrate and potassium phosphorus-1,1-dithiolates (di-sec-butyl and di-iso-butyl) in methanol yields 2:1 complexes which were characterized by FT-IR and NMR spectroscopy. 2:1 pyrazole adducts of both compounds were also obtained.The X-ray diffraction analysis of the compounds reveals square planar, four-coordination geometry for the homoleptic compounds and a six-coordinated distorted octahedral geometry for the adducts. In Ni[S2P(OBus)2]2 the molecules are associated through C-H?O hydrogen bonds (2.652 Å), and in Ni[S2P(OBui)2]2 the molecules are associated through C-H?S hydrogen bonds (2.948 Å). The pyrazole adducts are associated through N-H?O bonds and N-H?S bonds from the pyrazole nitrogen atoms, to form supramolecular assemblies. Thus, Ni[S2P(OBus)2(Pz)2]2 (Pz = pyrazole) forms bi-dimensional layers through N-H?O and N-H?S bonds (2.502 and 2.965 Å, respectively), whereas Ni[S2P(OBui)2(Pz)2]2 forms linear chains with N-H?S bonds 2.728 Å. The dithiophosphato groups behave as isobidentate chelating ligands. 相似文献
73.
Jeffrey P. Wikstrom Richard J. Staples Elena V. Rybak-Akimova 《Inorganica chimica acta》2010,363(5):884-714
Four nickel complexes each containing an R-2,2′-dipicolylamine ligand species (RDPA; R = benzyl, isopropyl, or tert-butyl) were synthesized and structurally characterized. In the absence of an interfering coordinating counterion, BzDPA and iPrDPA form 1:2 nickel:ligand complexes, with two facial ligands completing an pseudooctahedral nickel(II) coordination environment. In contrast, the sterically hindered tBuDPA ligand instead forms 1:1 metal:ligand complexes, even in the absence of associating counterions. Two novel tBuDPA nickel complexes with different counterions are described: nickel(II) chloride gives rise to an unusual 2Ni-3Cl dimer complex, while nickel(II) nitrate affords a 1:1 nickel:ligand complex which crystallizes with both fac and mer conformations in the same unit cell. 相似文献
74.
Nickel-induced Inhibition of Wheat Root Growth is Related to H2O2 Production, but not to Lipid Peroxidation 总被引:1,自引:1,他引:0
Effects of exogenous nickel (Ni: 10 and 200 μM) on growth, mitotic activity, Ni accumulation, H2O2 content and lipid peroxidation as well as the activities of various antioxidative enzymes, such as superoxide dismutase (SOD),
catalase (CAT), ascorbate peroxidase (APX) and glutathione peroxidase (GSH-Px) were investigated in wheat roots. A considerable
Ni accumulation in the roots occurred at both the concentrations. Although Ni at 10 μM did not have any significant effect
on root growth, it strongly inhibited the root growth at 200 μM. Mitotic activity in the root tips was not significantly affected
by exposure of the seedlings to 10 μM Ni; however, it was almost completely inhibited at 200 μM treatment. Ni stress did not
result in any significant changes in CAT and APX activities as well as lipid peroxidation. However, H2O2 concentration increased up to 82% over the control in the roots of seedlings exposed to 200 μM Ni. There was a significant
decline in both SOD (50%) and GSH-Px (20–30%) activities in the roots when the seedlings were treated with 200 μM Ni. The
results indicated that a strong inhibition of wheat root growth caused by Ni stress was not due to enhanced lipid peroxidation,
but might be related to the accumulation of H2O2 in root tissue. 相似文献
75.
Tuning the substituents of triazoles, we obtained di- and tri-nuclearic triazole-nickel complexes [Ni2(deatrz)4(H2O)5](SO4)2 · 7H2O (1) and [Ni3(dmtrz)6(H2O)6](SO4)3 · 21H2O (2) (deatrz = 3,5-diethanyl-4-amino-1,2,4-triazole; dmtrz = 3,5-dimethanyl-1,2,4-triazole). The X-ray single-crystal diffraction results reveal that sulfate anions and water clusters form supramolecular networks in both complexes. In 1, a supramolecular two-dimensional structure was fabricated by nano-sized grid with novel tetramer water rings templated via binuclear-nickel(II) cations, while in 2, water molecules and sulfate anions construct the first sulfate-water three-dimensional supramolecular network as host to encapsulate trinuclear-nickel guests. 相似文献
76.
Anita Rybka S?awomir Domaga?a Jerzy Mroziński Bohdan Korybut-Daszkiewicz 《Inorganica chimica acta》2006,359(14):4526-4534
Series of NiII and CuII complexes with dianionic [N2O2] ligands were synthesized and characterised applying spectroscopic and X-ray diffraction techniques. The ligands were obtained by 1:2 condensation of ethylene- and propylenediamine with malonic aldehyde derivatives (R2 = H, R1 = H or OCH3). Although the molecular formulae of the complexes are quite similar, the X-ray investigations have proved a significant structural diversity in the solid state. Among others, we found some simple nearly planar molecules stacked in the crystal lattice with electron density of six-membered rings delocalised over the chelate rings as well as some very complex polymeric or nickel acetate bridged trinuclear complexes. The coordination of the nickel ion by surrounding oxygen and nitrogen atoms is square-planar in the simplest case and octahedral in the most complex one. Small topological differences in similar molecules generate completely different crystal structures.From magnetic studies, a small, negative value of J obtained confirms the occurrence of weak antiferromagnetic interactions between the NiII ions in polymeric chain of the propylenediamine dialdehyde substituted derivative. 相似文献
77.
Two novel ion-pair complexes, [RBzIQl]+[Ni(mnt)2]− (mnt2− = maleonitriledithiolate, [RBzIQl]+ = 4-R-benzylisoquinolinium; R = H (1), Cl (2)) have been characterized structurally and magnetically. The anions and [BzIQl]+ cations of 1 form 1D column of alternating between cations and anions via π?π stacking interaction between Ni(mnt)2 plane and isoquinoline ring, and the Ni(mnt)2 anions between adjacent columns exist C?N, C?N, and N?N interaction. The anions and cations of 2 stack into well-segregated columns in the solid state; and the Ni(III) ions form a 1D zigzag chain in a Ni(mnt)2 column through intermolecular Ni?S, S?S, Ni?Ni or π?π interactions. The chain is uniform in 2 with the Ni?Ni distances of 3.784 Å. Magnetic susceptibility measurements for these complexes in the temperature range 1.8-300 K show that 1 exhibits antiferromagnetic coupling behavior, and 2 exhibits unusual magnetic phase transitions around 45 K. The overall magnetic behavior for 2 indicates the presence of antiferromagnetic interaction in the high-temperature phase (HT) and spin gap in the low-temperature phase (LT). 相似文献
78.
Matkar SS Wrischnik LA Jones PR Hellmann-Blumberg U 《Biochemical and biophysical research communications》2006,343(3):754-761
Nickel is considered a weak carcinogen. It is known to interact with DNA and DNA-binding proteins. The ability of certain nickel compounds to cleave DNA has been exploited mainly for research purposes and less for developing new anticancer drugs. Here we compare the interactions of two closely related nickel complexes, [NiCR]2+ and [Ni(CR-2H)]2+, with DNA. CR stands for 2,12-dimethyl-3,7,11,17-tetraazabicyclo-[11.3.1]-heptadeca-1(17),2,11,13,15-pentaene. [NiCR]2+ has been used in the past as a structure-specific probe for RNA and DNA oligonucleotides in the presence of oxidizing agent but little is known about the biological effects of either complex. Our results show that [Ni(CR-2H)]2+ can damage DNA in vivo and in vitro in the absence of an added oxidizing agent and has an IC50 of 70 microM in human breast cancer cells whereas [NiCR]2+ and NiCl2 do not exhibit significant cytotoxicity. However, both [NiCR]2+ and [Ni(CR-2H)]2+ bind to the minor groove of double-stranded DNA. 相似文献
79.
Industrial discharges from manufacturing streptomycin sulfate (SS) are inhibitory to biological wastewater treatment and need to be stripped of residual SS. For effective SS recovery from the wastewater, a two-stage foam separation technology was investigated using a column with a vertical ellipsoid-shaped channel (VEC) and a conventional one, and sodium dodecyl sulfate (SDS) served as the collector. The mechanism of enhancing foam drainage by VEC was theoretically analyzed. In the first stage, the column with VEC was used and under the optimal conditions of the liquid-loading volume 300 mL, volumetric airflow rate 100 mL/min, the initial pH 7.0 and the molar ratio of SDS to SS 8.0, an improved SS enrichment ratio of 16.7 was obtained. In the second stage, a conventional column was used and with a volumetric airflow rate of 450 mL/min, the foamate had a SS concentration of about 0.5 g/L, so it was used as the feed solution of the first stage. By the two-stage technology, the total SS recovery percentage reached as high as 99.7%. Thus, it was significantly effective for the two-stage foam separation technology to recover SS from the simulative wastewater. 相似文献
80.
Low-temperature, single crystal X-ray structural characterisations of trans-[NiCl2(HOMe)4], trans-O-[Ni(MeOH)2(μ-Cl)(2/2)2](∞∣∞) · 0.5dioxan and trans-trans-[Ni(H2O)2Cl2(O-dioxan-O)(2/2)](∞∣∞) · dioxan are recorded, offering intriguing insights into O-donor/Ni(II) relativities. All nickel atoms in all structures are located on crystallographic inversion centres, the last two compounds being one-dimensional polymers. 相似文献