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171.
S Nochi N Shimomura T Hattori T Sato Y Miyake K Tanizawa 《Chemical & pharmaceutical bulletin》1989,37(10):2855-2857
It was found that [4-(2-succinimidoethylthio)phenyl 4-guanidinobenzoate]methanesulfonate (E-3123) inhibits trypsin, thrombin and kallikrein, and its inhibitory activity is most potent toward trypsin. The interactions of these enzymes with E-3123 were studied mainly by using stopped-flow spectrophotometry. E-3123 behaved as a quasi-substrate of the enzymes and the inhibitory property was due to the efficient production of the stable acyl-enzyme. The acylation process with trypsin was exceedingly effective, and the resulting acyl-enzyme was the most stable among the three enzymes tested. This observation affords a rational basis for explaining the action of E-3123, which is a transient inhibitor most active toward trypsin. 相似文献
172.
A short synthesis of dragmacidin B (1), 2,5-bis(6'-bromo-3'-indolyl)piperazine (2), and corresponding didebromo analogues 8 and 9 is described. The key steps involve the dimerization of oxotryptamines 4 and 11 to give bis(indolyl)pyrazines 5 and 12, which upon selective reduction and reductive methylation with sodium cyanoborohydride afforded the requisite piperazine natural products. 相似文献
173.
Hiroyuki Matsumura Kimito Okumura Takahiro Shimamura Na-oki Ikenaga Takanori Miyake Toshimitsu Suzuki 《Journal of molecular catalysis. A, Chemical》2006,250(1-2):122-130
A possibility of antimony oxide as a catalyst for the selective oxidation of methane with oxygen to formaldehyde was investigated. The activity measurement was carried out at an atmospheric pressure and at 873 K, where the homogeneous gas-phase reaction was negligible. Oxidized diamond (O-Dia)-supported antimony oxide catalyst produced 1.3 mmol h−1 g-cat−1 of formaldehyde with a formaldehyde selectivity of 23%. On the other hand, SiO2 supported antimony oxide catalyst exhibited negligible catalytic activity. XRD and UV–vis analyses revealed that -Sb2O4 was formed on the oxidized diamond while Sb6O13 was formed on SiO2. Selective oxidation of methane to formaldehyde seemed to proceed on -Sb2O4 with moderate activity and selectivity to formaldehyde, via a redox cycle of -Sb2O4 and Sb2O4−x. On the other hand, Sb6O13 on SiO2 was stable under the reaction conditions and the selective oxidation occurred only slightly. 相似文献
174.
Shunsuke Nishimoto Stefanus Harjo Takashi Kamiyama Michihiro Miyake 《Journal of solid state chemistry》2006,179(6):1892-1897
A deuterated n=1 Ruddlesden-Popper compound, DLnTiO4 (HLnTiO4, Ln=La, Nd and Y), was prepared by an ion-exchange reaction of Na+ ions in NaLnTiO4 with D+ ions, and its structure was analyzed by Rietveld method using powder neutron diffraction data. The structure analyses showed that DLaTiO4 and DNdTiO4 crystallized in the space group P4/nmm with a=3.7232(1) and c=12.3088(1) Å, and a=3.7039(1) and c=12.0883(1) Å, respectively. On the other hand, DYTiO4 crystallized in the space group P21/c with a=11.460(1), b=5.2920(4), c=5.3628(5) Å and β=90.441(9)°. The loaded protons were found to statistically occupy the sites around an apical oxygen of TiO6 octahedron in the interlayer of these compounds, rather than Na atom sites in NaLnTiO4. 相似文献
175.
Jun-Ichi Matsumoto Teruyuki Miyamoto Akira Minamida Yoshiro Nishimura Hiroshi Egawa Haruki Nishimura 《Journal of heterocyclic chemistry》1984,21(3):673-679
Fluorination of the 2,6-disubstituted 3-aminopyridines 5 and 12 by the Balz-Schiemann reaction is described. 2,6-Dichloro-3-pyridinediazonium tetrafluoroborate ( 6 ) and 2-substituted 6-acetylamino-3-pyridinediazonium tetrafluoroborates 13 were heated with or without a solvent to give the corresponding fluorinated pyridines 7 and 14 , respectively, in good yields. 2-Substituted 6-acetylamino-3-fluoropyridines ( 14 ) were converted by a known method into a series of 7-substituted 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-1,8-naphthyridine-3-carboxylic acids 21 including enoxacin [1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-1,8-naphthyridine-3-carboxylic acid [( 2 )], a new potential antibacterial agent. 相似文献
176.
T Miwa S Sakashita H Ozawa J Haginaka N Asakawa Y Miyake 《Journal of chromatography. A》1991,566(1):163-171
An ovomucoid-conjugated polymer column was prepared for the liquid chromatographic resolution of racemic compounds. The column showed strong retention of acidic solutes, a characteristic attributed to the structure of the stationary phase support gel. Although the efficiency of the column was lower than that of an ovomucoid-conjugated silica gel column, enantiospecific chlorprenaline determination in plasma was achieved with solute amounts from 1.0 ng to 0.1 microgram. 相似文献
177.
Brown CN Cooper WE Finley D Hsiung YB Jonckheere AM Jostlein H Kaplan DM Lederman LM Moreno G Hemmi Y Imai K Miyake K Nakamura T Sasao N Tamura N Yoshida T Maki A Sakai Y Gray R Luk KB Rutherfoord JP Straub PB Williams RW Young KK Adams MR Glass H Jaffe D McCarthy RL Crittenden JA Smith SR 《Physical review letters》1989,63(24):2637-2640
178.
179.
180.
Kiyoshi Toda Mitsunori Miyake Hisao Ohtake 《Applied biochemistry and biotechnology》1990,26(2):139-149
A new process of biological waste treatment was developed by use of microbial films grown on the liquid surface in a shallow flow reactor. The performance of this process was tested using a synthetic waste that contained acetic acid as a model organic pollutant. About 90% of acetic acid (10,000 mg/L-1) in the synthetic waste was removed by setting alpha tau: (alpha specific liquid surface area, cm-1, and tau: hydraulic liquid detention time, h) higher than 15 cm-1/h. It was necessary to maintain alpha large enough (more than 10 cm-1 in most cases) to satisfy oxygen demand for the biooxidation. The oxygen balance and TOC determinations showed that the acetic acid removed was completely oxidized with oxygen transferred through the liquid surface. This process would contribute to energy savings, since it requires no forced aeration for oxygen supply. 相似文献