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1.
We have examined the oxidation of N,N′-bis(4-aminophenyl)-N,N′-dimethylethylenediamine (BED) by tissue homogenates and fractions of liver homogenates. We find that this agent both gives osmiophilic deposits in tissue blocks and readily increases the uptake of oxygen by hepatic homogenates. The highest activity was in the mitochondrial and, next, in the microsomal fractions. Kinetic evidence indicates that the former represents two enzymatic activities while the latter is only a single site. The activity was greatest in the outer membrane of the mitochondria, in agreement with electron micrographic studies and in the rough microsomal fraction. Further, it was very sensitive to both formaldehyde and detergents. The activity was not well associated with either monamine oxidase (benzylamine substrate) or xanthine oxidase activities. Activity was observed in a large number of tissues.  相似文献   

2.
The platinum(II) complexes of the formula [Pt(DCHEDA)X2], where DCHEDA is N,N′-dicyclohexylethylenediamine and X is CL, Br, I, 0.5C2O42− (oxalate), 0.5C3H2O42− (malonate), 0.5C9H4O62− (4-carboxyphthalate), 0.5S2O32− or 0.5SO42−, have been synthesized and characterized by UVVis, IR, and 1H NMR spectral techniques. All the above complexes are non-electrolytes in DMF/H2O, except the sulphate complex which becomes a 1:1 electrolyte after incubation for 24 h at 28 °C. The halide complexes were also studied by X-ray photoelectron spectroscopy and these data suggest that there is π-bonding from platinum to halide in these complexes. The oxalate, malonate and sulphate bind in their complexes as bidentate ligands to platinum through two oxygen atoms whereas the thiosulphate in its complex binds as a bidentate ligand to platinum through one oxygen atom and one sulphur atom.  相似文献   

3.
Synthesis of complexes cis,cis-WVOXL (X=Cl, NCS), cis,trans-WVOXL (X=Cl, OPh, SPh) and cis,trans-WVIE2L (E2=O2, OS, S2) of the title ligand LH2 are reported. cis,cis-WVOCIL crystallises in space group P21/c with a=13.6541(9) Å, b=7.1555(11) Å, c=18.198(2) Å, β=95.294(6)°, V=1770.4(3) Å3 and Z=4 while the cis,trans isomer crystallises in space group P21/n with a=10.361(3) Å, b=14.141(4) Å, c=12.213(5) Å, β=102.56(3)°, V=1747(2) Å3 and Z=4. cis,trans-WVIS2L crystallises in space group P21/n with a=10.645(2) Å, b=13.929(2) Å, c=12.189(2) Å, β=103.14(2)°, V=1760(1) Å3 and Z=4. A short CH3···Cl distance of 3.067(7) Å and an acute OWCl angle of 94.1(2)° are seen in cis,cis-WVOClL, which converts to the cis,trans form on heating in MeCN. The latter isomer features a CH3···Cl distance of 3.38(2) Å and an OWCl angle of 105.1(8)°. Electrochemical and EPR data are reported. In particular, cis,trans-WVIE2L may be reduced to [WVE2L]. EPR properties of these anions and those of complexes WVOXL are discussed in the context of WV centres in tungsten enzymes.  相似文献   

4.
[Pt(COD)Cl2] (COD=1,5-cyclooctadiene) is a versatile starting material for the synthesis of Pt(II) compounds. The preparations of the new compounds [Pt(COD)Cl(NO3)], [Pt(COD)(NO3)2] and [Pt(PPh3)3(NO3)](NO3) and also of the known compounds cis[Pt(PPh3)2Cl2], cis [Pt(PPh3)2Cl(NO3)], cis[Pt(PPh3)2(NO3)2] and [Pt(PPh3)3Cl](NO3)are reported. The compounds are characterized by elemental analysis, 31P{1H} NMR spectroscopy and IR spectroscopy.  相似文献   

5.
Ten dioxide species derived from N,N′-bis(alkylmethyl)-1,2-ethanediamine and N,N′-bis(alkylmethyl)-1,2-propanediamine were tested for their activity withStaphylococcus aureus, Escherichia coli andCandida albicans. A relation between the length of the alkylchain, and/or the molecule asymmetry, and the antimicrobial activity was found. Part V of the series Amine Oxides; part IV: Mlynarciket al.: Folia Microbiol. 24, 188 (1979).  相似文献   

6.
Antibacterial effect of 17 ammonium compounds of the type of N,N′-bis(alkyldimethyl)-α,ω-alkanediammonium dibromides was tested on anaerobically sporulating bacteria of the genusClostridium. A sizable antibacterial activity was displayed by five N,N′-bis(alkyldimethyl)-1,6-hexanediammonium dibromides and by four N,N′-bis(decyldimethyl)-α,ω-alkanediammonium dibromides. These compounds exhibited activity higher than, or comparable with, that of the reference standards Ajatin and Septonex. The maximum antibacterial activity was found in compounds whose alkyl chain contained 9–12 carbon atoms. Compounds with a lower number of carbon atoms in the chain (less than 8) exhibited a low activity.  相似文献   

7.
8.
Summary Male mice SAS/4 were injected i.v. with239Pu citr(IV) 0.27 µCikg–1–9.99 kBqkg–1. After 1 h 30 µmol kg–1 of 3,4,3 LICAM(C), N, N, N, N-tetra-(2,3-dihydroxybenzoyl)-spermine or Na3CaDTPA as a reference compound was given intraperitoneally. After 4 days the animals were sacrified and the Pu content in livers, kidneys, femurs and carcasses was determined by the liquid scintillation method. It was found that, as compared with the control, 3,4,3 LICAM(C) removed 83% of the Pu activity deposited in the liver, 71% of that in the femur and 79% of the Pu in the whole body. The Pu content in the kidneys exceeded the control value by about 50%. Na3CaDTPA removed 96, 86, 40 and 72% of plutonium from the liver, kidneys, femurs and carcasses respectively.Tetra-DHB-spermine caused the excretion of 50, 57 and 39% of Pu from liver, bone and whole body respectively. The retention of Pu in the kidneys was increased to 400% of the control value.  相似文献   

9.
Iron chlorosis is commonly corrected by the application of EDDHA chelates, whose industrial synthesis produces o,oEDDHA together with a mixture of regioisomers and other unknown by-products. HJB, an o,oEDDHA analogous, is a new chelating agent with a purer synthesis pathway than EDDHA. The HJB/Fe3+ stability constant is intermediate between the racemic and meso o,oEDDHA/Fe3+ stereoisomers. This work studied the efficacy of HJB as a Fe source in plant nutrition. No significant differences between o,oEDDHA/Fe3+, HJB/Fe3+ and HBED/Fe3+ were observed when they are used as substrates of the iron-chelate reductase of mild chlorotic cucumber plants. Chelates prepared with the stable isotope 57Fe were used in both soil and hydroponic experiments. In the hydroponic experiment, nutrient solutions with low doses of chelates were renewed weekly. Soybean plants treated with o,oEDDHA/57Fe3+ recorded the highest results in biomass, SPAD index and Fe nutrition. In the soil experiment, chelates were added once at a rate of 2.5 mg Fe per kg of a calcareous soil. Soybean plants treated with HJB/57Fe3+ recorded a higher biomass and SPAD index in young leaves than the plants treated with o,oEDDHA/57Fe3+; however, 57Fe and total Fe concentrations in leaves were lower. The results of both pot experiments are associated with a faster ability by o,oEDDHA to provide Fe to the plants and with a more continuous supply of Fe from HJB/Fe3+. HJB/57Fe3+ effectively alleviated the Fe-deficiency chlorosis of soybean with a longer lasting effect than o,oEDDHA/57Fe3+.  相似文献   

10.
The distribution of O-(1,2-diacylglycero)-4-(N,N,N-trimethyl)homoserine (DGTS), a betaine lipid, in ten samples of plants belonging to the division Lycopodiophyta collected in various habitats was studied. Homogeneous plant tissues (vegetative shoots and spikelets) and mixed tissues (shoots with spikelets) were analyzed. A particular attention was paid to the DGTS-synthesizing ability of various club mosses, various tissue types forming an organ in a single plant species, as well as the ratio between DGTS and other glycerolipid classes.  相似文献   

11.
Myeloperoxidase is the main peroxisomal protein of neutrophils, monocytes, and a subpopulation of tissue macrophages; it plays the key role in protective and inflammatory responses of the organism. This role is mediated by various diffusible radicals formed during oxidative reactions catalyzed by the enzyme heme. Myeloperoxidase and nitric oxide synthase are stored in peroxisomes. Nitric oxide reacts with the heme of myeloperoxidase. Low nitric oxide concentrations increase peroxidase activity through reduction of Compound II to native myeloperoxidase. Conversely, high nitric oxide concentrations inhibit the catalytic activity of myeloperoxidase through formation of inactive nitrosyl–heme complexes. Such effect of nitric oxide on catalytic activity of myeloperoxidase has various consequences for infectious and local inflammatory processes. Another oxide of nitrogen, nitrite, is a good substrate for myeloperoxidase Compound I but slowly reacts with Compound II. Nitrogen dioxide is formed after nitrite oxidation by myeloperoxidase. Formation of nitrogen dioxide is another protective mechanism and nitration of microbial proteins by myeloperoxidase can represent an additional protective response of peroxisomes.  相似文献   

12.
The title compound, Fe(salen)NO3, was reacted with imidazole, 1-methylimidazole, piperidine, and morpholine in either chloroform or dichloromethane solution. The reactions were monitored with proton NMR and electronic spectra and conductance measurements. The imidazole bases appeared to react with the complex in a 2:1 fashion with displacement of the nitrate, producing a high-spin iron(III) complex. The secondary amines promoted hydrolysis with any trace water present to form [Fe(salen)]2O. The chloro complex, Fe(salen)Cl, did not react with the imidazole bases, but did form the μ-oxo complex when a large excess of piperidine was present. The N,N′-phenylenebis-(salicylideneimine) complex, Fe-(salphen)NO3, was found to precipitate from an imidazole (im) chloroform solution as the high-spin complex, Fe(salphen)NO3·2im.  相似文献   

13.
The study has been designed to investigate the anti-diabetic effects of cesium aqua (N,N′-ethylene (salicylideneiminato)-5-sulfonato) oxovanadium (IV) dihydrate (VO(salen-SO3)), an organic vanadium compound, in streptozotocin-induced diabetic rats. VO(salen-SO3) was orally administrated to diabetic rats at the dose of 0.3 mg/ml through drinking water for 24 days. Blood glucose level was significantly declined, and oral glucose tolerance was improved after VO(salen-SO3) treatment. Moreover, liver and muscle glycogen concentrations were markedly increased in VO(salen-SO3)-treated diabetic rats. On the other hand, aspartate amino transferase and blood urea nitrogen in serum were significantly decreased after treatment with VO(salen-SO3). Take together, these results suggested that VO(salen-SO3) may be of potential value in the therapy of diabetic symptom and hyperglycemia-induced hepatic and renal dysfunction.  相似文献   

14.
15.
《Inorganica chimica acta》1986,114(2):151-158
CoX2(NO)(PMe3)2 complexes (X = Cl, Br, I, NO2) exhibit markedly different ν(NO) stretching frequencies and different geometries. The structure of CoI2(NO)(PMe3)2 (1) and CoCl2(NO)(PMe3)2 (2) have been determined by X-ray diffraction. Both crystallize in the orthorhombic system, Pnma space group with four molecules in a cell of the following dimensions: for 1, a = 10.497(2), b = 10.694(2), c = 13.975(2) Å, ν= 1568.8, Å3; for 2, a = 9.607(2), b = 10.689(2), c = 13.512(3) Å, ν= 1387.5 Å3. The structures were refined to conventional R values of R = 0.040 from 1630 reflections for 1 and R = 0.033 from 976 reflections for 2. In both cases, the coordination geometry about the five-coordinate cobalt atom is approximately trigonal bipyramidal, with the NO group sharing the equatorial positions with the halide ligands. Structure 2 is disordered, which prevents any precise structural characterization. In (1), the CoNO angle is 179.2(19)° and the Co NO distance is 1.728(23) Å; v(NO) is 1753 cm−1. CoCl2(NO)(PMe3)3 shows a v(NO) vibration at 1637 cm−1. Co(NO2)2(NO)(PMe3)2 with v(NO) = 1658 cm−1 has been proposed as a square pyramidal structure with a bent apical CoNO. These differences in NO stretching frequencies and geometries are discussed.  相似文献   

16.
The observation of 2h J iso(N, N) coupling has prompted considerable interest in this phenomenon from experimentalists and theoreticians due to the potential these couplings hold for the determination of secondary and tertiary structure in biologically important molecules. Here, we present an ab initio (MCSCF) study of the complete 2h J(N, N) tensor for a model methyleneimine dimer system as a function of (i) the N-N separation, r NN, and (ii) the hydrogen bond angle, . This simple system models the 2h J(N, N) tensor of nucleic acid base pairs. Results indicate that although the Fermi-contact mechanism dominates 2h J iso(N, N), the coupling tensor is anisotropic due to contributions from the Fermi-contact spin-dipolar cross term. The variation in 2h J iso(N, N) as a function of r NN is fit to an exponential decay. The influence of on the coupling constant is less pronounced but must be considered if experimental coupling constants are to be used for quantitative structure determination. Our results for this simple model system demonstrate that 2h J iso(N, N) is a valuable probe of hydrogen bonding in nucleic acid base pairs.  相似文献   

17.
Abstract

2,3′-Anhydro-2′-deoxy-5′-0-(triphenyl methyl) and 5′-0-(monomethoxytriphenylmethyl) pyrimidine nucleosides of uracil, thymine, and cytosine were synthesized in a single step from their 2′-deoxy-5′-0-(triphenylmethyl) or 5′-0-(monomethoxytriphenylmethyl) precursors using N,N-diethylaminosulfur trifluoride (DAST). The anhydronucleosides were either isolated or directly converted to their respective 2-deoxy-β-D-threo-pentofuranosyl nucleosides using sodium hydroxide in ethanol.  相似文献   

18.
Edward B. Tucker 《Planta》1990,182(1):34-38
The effect of microinjected calcium-loaded 1,2-bis(2-aminophenoxy) ethane-N,N,N,N-tetraacetic acid (CaBAPTA) on cell-to-cell diffusion of carboxyfluorescein (CF) was examined in staminal hairs of S. purpurea Boom. The CaBAPTA was microinjected into the cytoplasm of the staminal hairs either with CF or prior to a subsequent microinjection of CF. The cell-to-cell diffusion of CF along the hair was monitored using enhanced-fluorescence video microscopy. Cytoplasmic streaming stopped in cells treated with CaBAPTA, indicating that intracellular Ca2+ had increased. Cell-to-cell diffusion of CF was blocked in cells treated with Ca-BAPTA. An inhibition of cytoplasmic streaming and cell-to-cell diffusion was observed in the cells adjoining the CaBAPTA-microinjected cell, indicating that the Ca-BAPTA appeared to pass through plasmodesmata. While cytoplasmic streaming resumed 5–10 min after CaBAPTA treatment, cell-to-cell diffusion did not resume until 30–120 min later. These data support an involvement of calcium in the regulation of cell-to-cell communication in plants.Abbreviations BAPTA 1,2-bis(2-aminophenoxy)ethane-N,N,N, N-tetraacetic acid - CF carboxyfluorescein This work was supported by Professional Staff Congress-City University (PSC-CUNY) of New York grant No. 667180 and U.S. Department of Agriculture grant No. 87-CRCR-1-244.  相似文献   

19.
A fluorescent analog of angiotensin II was synthesized by reacting fluorescein 5′-isothiocyanate with (Asp1, Ile5)-angiotensin II. Nα-(N-Fluoresceinthiocarbamoyl)-(Asp1, Ile5)-angiotensin II was purified by chromatography on DEAE-cellulose and Sephadex G-25. Analysis of the analog by thin-layer chromatography, thin-layer electrophoresis, and reversed-phase high-performance liquid chromatography indicated that the analog was free of angiotensin II and fluorescein 5′-isothiocyanate. N-Terminal sequence analysis demonstrated that fluorescein 5′-isothiocyanate reacted with the N-terminal aspartic acid residue of angiotensin II. Nα-(N-Fluoresceinthiocarbamoyl)-(Asp1, Ile5)-angiotensin II has an absorption maximum at 492 nm, and the value of the molar extinction coefficient, ?, is 7.7 × 104m?1 cm?1. The fluorescence emission maximum occurs at 520 nm. Infusion of the analog (0.69 μg/min/kg body wt) directly into the renal artery of an anesthetized rat reduced the blood flow by 12 to 27% within 2 min. Infusion of angiotensin II (0.48 μg/min/kg body wt) reduced renal arterial blood flow by 35 to 53% within 2 min. Saralasin, a partial agonist and antagonist of angiotensin II, inhibited the biologic effect of the fluorescent analog and angiotensin II by 75 and 70%, respectively. The purity, spectral properties, and in vivo biologic activity of Nα-(N-fluoresceinthiocarbamoyl)-(Asp1, Ile5)-angiotensin II indicate that this analog should facilitate characterization of angiotensin II receptors.  相似文献   

20.
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