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Takeshi Kitahara Keimei Fujimoto Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(8):1511-1514
The synthesis and biological activities of 2,2-dimethyl-3,3-dichlorocyclopropane carboxylic esters are descrived. 相似文献
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F. Rubio B.J. Miwa W.A. Garland 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1982,233(1):167-173
A method is described for measuring imidazobenzodiazepine-3-car☐yamide, a new anxiolytic agent, in human plasma. A tetradeuterated analogue of the analyte is used as the internal standard. The drug and its internal standard are (1) extracted from plasma at pH 9 with benzene containing 20% 1, 2-dichloroethane, (2) derivatized with pentafluoropropionic anhydride in the presence of triethylamine and (3) the nitrile derivative of the analyte and internal standard are analyzed by gas chromatography (GC)—negative chemical-ionization mass spectrometry (CIMS) using methane as both GC carrier gas and CI reagent gas. The mass spectrometer is set to monitor the intense (M-HCl)−- ions of imidazobenzodiazepine-3-nitrile and its tetradeuterated analogue atm/z 316 andm/z 320, respectively. Quantitation of an experimental plasma sample is based on the comparison of them/z 316 tom/z 320 ion ratio in each sample to that obtained from the analyses of control plasma spiked with various amounts of the drug and a fixed amount of internal standard. The limit of quantitation of the method is approximately 100 pg ml−1 of plasma and the precision (relative standard deviation) at a plasma concentration of 1 ng ml−1 is 4%. 相似文献
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Toshio Atsumi Toshitsugu Fukumaru Tomoya Ogawa Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(11):2621-2626
A novel synthesis of N-acetyllincosamine derivatives (3) and (14) was accomplished. 相似文献
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An azoreductase has been purified to apparent homogeneity from the hepatic 105,000 x g supernatant fraction of 3-methylcholanthrene-treated rats. In the presence of sodium dodecyl sulfate, the purified enzyme preparation electrophoreses on polyacrylamide gels as a single protein band with a molecular weight of 30,000. In the absence of detergent, chromatography of the azoreductase on Sephadex G-100 gives a molecular weight of about 52,000 suggesting that the native enzyme may exist as a dimer. The purified azoreductase has a typical flavoprotein absorption spectrum and contains 2 mol of FAD/mol of enzyme. The enzyme catalyzes the reductive fission of methyl red (2'-carboxy-4-N,N-dimethylaminoazobenzene) and a structure-activity study indicates that the 2'-carboxyl group of methyl red is essential for catalysis since other structurally related analogs are totally inactive. 相似文献
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Summary We describe a genetic polymorphism of a human cellular polypeptide with mol. wt. 100,000, detected in peripheral blood lymphocytes by high resolution two-dimensional electrophoresis. Three different electrophoretic types (1-1, 2-1, and 2-2) of the polypeptide have been identified. Family and population studies indicate that the three phenotypes of the polypeptide are determined by two common alleles at a single autosomal locus. The polypeptide occurs in the cytosol and is one of the abundant polypeptides of B-lymphoblastoid cells, T-lymphoblastoid cells, fibroblasts, and HeLa cells. The data indicate that the cytosol polypeptide with mol.wt. 100,000 shows a genetic polymorphism determined by aew autosomal locus. It is proposed that the polypeptide and its locus be temporarily designated cytosol 100k polypeptide (C100k polypeptide) and C100P, respectively. In a Japanese population, the gene frequencies of C100P
1 and C100P
2 were 0.907 and 0.093, respectively. 相似文献
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par Masanao Matsui Yôichi Nakatani Yasuki Mori et Zirô Nikuni 《Bioscience, biotechnology, and biochemistry》2013,77(9):647-649
The synthesis of 3-hydroxymethyl-4,5,7-trimethoxy-2-naphthoic acid lactone (II) is described. 相似文献