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21.
Kamoda S Nomura C Kinoshita M Nishiura S Ishikawa R Kakehi K Kawasaki N Hayakawa T 《Journal of chromatography. A》2004,1050(2):211-216
Carbohydrate chains in glycoprotein pharmaceuticals have important roles for the expression of their biological activities. Therefore, development of an assessment method for the carbohydrate chains is an important parameter for quality control of glycoprotein pharmaceuticals such as newly developed therapeutic antibodies. In this report, we applied capillary electrophoresis with laser-induced fluorescence detection to the analysis of carbohydrate chains after releasing with glycoamidase followed by derivatization with 3-aminobenzoic acid. We found that four major oligosaccharides present in antibody pharmaceuticals were successfully separated with good resolution. The present method showed good precision in both migration times and relative peak areas, and gave comparable accuracy with that using a derivatization method with 8-aminopyrene-1,3,6-trisulfonate. 相似文献
22.
Satoru Hommura Yasuhiro Kunisa Ichiro Terada Masaru Yoshitake 《Journal of fluorine chemistry》2003,120(2):151-155
Characteristics of fibril reinforced membranes developed by Asahi Glass Company are reviewed. PTFE-fibrils <1 μm in diameter are dispersed in ion-exchange membranes uniformly. Mechanical properties, such as tensile strength, tear strength, creep property and compressive property were examined and compared with non-reinforced membranes. Fibril reinforced membranes, even by the addition of a small amount of PTFE-fibrils (2.7 wt.%), show excellent mechanical strength, especially in creep and tear strength. Cell performance is nearly equal to the one using a non-reinforced membrane and cell voltage stays about the same during the cell operation at 80 °C for 3000 h. 相似文献
23.
Lin Wang Shinji Takeoka Eishun Tsuchida Satoru Tokuyama Takahiro Mashiko Tadashi Satoh 《先进技术聚合物》1992,3(1):17-21
The carbonyl hemoglobin (CO-Hb), which was used to prevent denaturation (metHb) during the preparation of samples, was encapsulated into lipid vesicles constituted from unsaturated phospholipid, cholesterol and unsaturated fatty acid. Unsaturated components were polymerized by γ-irradiation to enhance the stability of bilayer membrane. An aqueous dispersion of resulting Hb vesicles was freeze-dried in the presence of saccharides (50–200 mM) to obtain a dehydrated powder of Hb vesicles. Change in the vesicle size, the leakage of encapsulated Hb and the oxidation of Hb to metHb were not observed. Therefore, the long-term storage of Hb vesicles can be realized as a dry powder. 相似文献
24.
- and -dialkylvinyloxyboranes, prepared directly from cyclohexyl ethyl ketone, undergo stereo-selective aldol condensations to provide - -β-hydroxy-α-methylketones, respectively. 相似文献
25.
Satoru Kobayashi 《Tetrahedron》2008,64(41):9705-9716
Cross-conjugated azatrienes bearing an electron-withdrawing sulfonyl or benzoyl group on the nitrogen atom underwent, on heating or in the presence of a Lewis acid (TMSOTf), an initial inverse electron-demand hetero Diels-Alder reaction with electron-rich dienophiles (vinyl ether, vinyl thioether, and allenyl ether) to produce 1:1 cycloadducts with high endo selectivity. The initial cycloadducts thus obtained underwent a second Diels-Alder reaction stereoselectively on the newly formed diene unit with electron-deficient dienophiles to give the crossed bis-cycloadducts, octahydroquinolines, with high diastereo-π-facial selectivity. The N-sulfonylazatrienes tethering an ortho-cinnamyloxyphenyl dienophile at the triene terminal underwent an initial intramolecular hetero Diels-Alder reaction of the inverse electron-demand type. The subsequent second Diels-Alder reaction of the formed mono-cycloadducts completed the diene-transmissive hetero Diels-Alder protocol to give benzopyrano[3,4-c]quinolines in a highly stereoselective manner. 相似文献
26.
Kitani S Sugawara K Tsutsumi K Morimoto T Kakiuchi K 《Chemical communications (Cambridge, England)》2008,(18):2103-2105
3-Arylthiochromone derivatives were synthesized as new photolabile protecting groups, in which the photoreactivity was switchable based on oxidation of the sulfur atom (sulfide and sulfone); the protected substrates , released the corresponding alcohols, amines or carbonxylic acids almost quantitatively under UV-light in neutral condition and the photoproduct showed high fluorescence intensity. 相似文献
27.
Ochiai M Tada N Murai K Goto S Shiro M 《Journal of the American Chemical Society》2006,128(30):9608-9609
Stable aliphatic bromonium ylides (RfSO2)2C--Br+C6H4-p-CF3 (Rf = CF3, CF3(CF2)3) have been synthesized and structurally characterized for the first time. X-ray crystallographic analyses indicated a ylide structure with an sp2 hybridization of the ylide carbanions and with little double-bond character for the ylidic bond. The bromonium ylides selectively undergo transfer of the aryl group to nitrogen heterocycles, such as pyridines, yielding N-arylpyridinium salts. This is in a marked contrast to the reaction of the iodonium ylides, which produces pyridinium ylides through transylidations. 相似文献
28.
Kiyoshi Tanaka Yasuhiro Yamamoto Hiroto Obara Satoru Iwata 《Supramolecular chemistry》2013,25(4):347-352
5,15- cis -bis(Ureidophenyl)porphyrins have significant recognizing ability for p -benzoquinones through four-point hydrogen bonding. Although an unusual temperature-dependence of the complexation is observed with bis( N '-phenylureidophenyl) porphyrin, bis( N '-ethylureidophenyl)porphyrin shows a satisfactorily linear van't Hoff plot and recognizes an electron-rich p -benzoquinone such as tetramethyl- p -benzoquinone more effectively, which is ascribed to the large enthalpy change in the complex. 相似文献
29.
Qingbin Xue Tatsumi Kimura Takashi Fukuda Satoru Shimada Hiro Matsuda Corresponding author 《Liquid crystals》2013,40(2):137-143
Chiral helical polymers have been expected to exhibit optical activity with a significantly large optical rotation power. In this paper polymethylphenylethylcarbodiimides (Poly-PhEMCDI) with helical structure were synthesized by the insertion polymerization of a corresponding chiral monomeric carbodiimide initiated by a copper complex. The circular dichroism spectra and optical rotation power induced by the ordered rigid main chain helical structure of polycarbodiimides, in solution and as cast films, were studied. Polycarbodiimides have a rigid rod helical structure and form lyotropic liquid crystal (LLC) in organic solvents such as dichloromethane (DCM), chloroform and THF. The LLC phase was studied using polarizing optical microscopy and X-ray diffraction. A chiral nematic phase was formed in DCM and chloroform in the concentration range 20–36%. Spherulites were formed in more concentrated solution. The formation of a LLC phase in polycarbodiimides organic solutions makes it possible to align the polymer helical chain to form an ordered film for electro-optical applications. 相似文献
30.
The title intermediate () is produced on photolysis of hexakis(2,6-diethyl-phenyl)cyclotrigermane () or bis(2,6-diethylphenyl)bis(trimethylsilyl)germane () as evidenced by trapping experiments, and thermally dimerizes to tetrakis(2,6-diethyl-phenyl)digermene (). Diarylgermylenes such as do not form stable triethylamine adducts (e.g. ) as has been previously reported. 相似文献