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《Analytical letters》2012,45(4):625-641
Abstract Pyrroline 5-carboxylate, a potent effector of redox dependent pathways, is a nutritionally responsive plasma constituent and is present in tissue culture medium conditioned by a variety of cells. Studies of P5C production and release both in vivo and in vitro have become increasingly important. To date, the assay used is a specific, sensitive radioenzymatic method. Unfortunately, the necessary materials (purified P5C reductase and NADP[3H], labeled in the transferable position) are not readily available. We now describe a method using commercially available reactants. This new method, based on the interaction of P5C with cysteine, is sensitive and specific; the presence of a wide variety of compounds only minimally affected the assay. [S35] Cysteine at a defined specific activity is reacted with P5C and the P5C-CYS adduct can be separated from the reactants by cation exchange column chromatography. To optimize the assay conditions, we characterized the time course, pH dependence and cysteine concentrations for adduct formation. Studies showed that the sulfhydryl group of cysteine is critical in the formation of the P5C-CYS adduct. Comparison of this new method to the previously published radioenzymatic method showed close correlation over a wide range of P5C concentrations in conditioned media. 相似文献
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Murat AltunkayaErgün Gonca 《Polyhedron》2011,30(6):1035-1039
Magnesium porphyrazinate substituted with eight 3,5-bis(trifluoromethyl)phenyl groups on the peripheral positions has been synthesized by the cyclotetramerization of 3,4-[3,5-bis(trifluoromethyl)phenyl]pyrroline-2,5-diimine in the presence of magnesium butanolate. Acid-mediated demetallation of the magnesium porphyrazine resulted in peripheral oxidation of one pyrrole ring to reveal the seco-porphyrazine, octakis[3,5-bis(trifluoromethyl)phenyl]-2-seco-porphyrazine-2,3-dione. Further reaction of this product with copper (II) acetate, zinc (II) acetate and cobalt (II) acetate has led to the metallo-derivatives, {octakis[3,5-bis(trifluoromethyl)phenyl]-2-seco-2,3-dioxoporphyrazinato} M(II) [M = Cu(II), Zn(II), Co(II)]. These new soluble complexes were characterized by elemental analysis, together with FT-IR, 1H NMR, 13C NMR, 19F NMR, UV-Vis and mass spectral data. 相似文献
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Qian Yang 《Tetrahedron letters》2006,47(23):3893-3896
The ring-closing metathesis (RCM) reactions of diallylamines occurred under controlled microwave irradiation. In addition to the high reaction rate, the key features of the reaction are that it can be carried out without deactivation of the substrates and without the use of Lewis acids. 相似文献
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《Journal of Coordination Chemistry》2012,65(17):2875-2882
By cyclotetramerization of 3,4-bis(4-tert-butylphenyl)pyrroline-2,5-diimine in the presence of magnesium butanolate, magnesium porphyrazinate with eight (4-tert-butylphenyl) units on the periphery has been synthesized. Its demetalation by the treatment with trifluoroacetic acid resulted in a partially oxidized product, namely, octakis(4-tert-butylphenyl)-2-seco-porphyrazine-2,3-dione. Further reaction of this product with copper(II) acetate, zinc(II) acetate, and cobalt(II) acetate led to the metallo derivatives, [octakis(4-tert-butylphenyl)-2-seco-2, 3-dioxoporphyrazinato]M(II) (M = Cu, Zn, Co). These soluble complexes have been characterized by elemental analysis, FT-IR, 1H NMR, UV-Vis, and mass spectral data. 相似文献
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The electron spin resonance spectra of N-carbamoyl-N-(l-oxyl-2,2,5,5-tetramethyl-pyrrolin-3-yl) urea compounds in ten solvents with different polarities were determined. It was found that the hyperfine splitting constant AN and spin density pN. as well as the energy difference between two adjacent energy levels E of different pyrroline nitroxides in the same solvent increase with the increase of electron-withdrawing α-bility of the substituted groups on the aromatic ring. There was a linear correlation between AN and Reichardt ET value, and between AN and Z value as well. Such a linear correlation was also found between solvent viscosity n and ESR rotational correlation time r. On the other hand, the correlation between T and the relative height hr of peak on high field was reverse. The results are discussed in the paper. 相似文献
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A simple and appropriate procedure for the synthesis of 4,5‐dihydro‐5‐hydroxy‐3H‐pyrrole‐3,3‐dicarbonitrile derivatives is reported. The advantages of this method are one‐pot conditions, high yield of products, short reaction times, and no need of metal catalyst. The structures are confirmed spectroscopically (IR, 1H‐ and 13C‐NMR, and EI‐MS) and by elemental analyses. A plausible mechanism for this reaction is proposed (Scheme 2). 相似文献
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本文合成19个新的N-(2,2,5,5-四甲基-3-吡咯啉-1-氧自由基)-N-(酰胺基)脲化合物.研究了此类化合物的ESR,MS及IR波谱性质.初步观察了此类化台物对白血病L7712癌细胞以及腹水型肝癌细胞的抑制作用.发现有的化合物抑制效果显著. 相似文献
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