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471.
Kinoshita E Yamada A Takeda H Kinoshita-Kikuta E Koike T 《Journal of separation science》2005,28(2):155-162
Immobilized metal ion affinity chromatography (IMAC) is now a widely accepted technique for the separation of natural or artificial products that is beginning to find industrial applications. Here, we introduce a novel procedure for the separation of phosphopeptides and phosphorylated proteins by immobilized zinc(II) affinity chromatography. The phosphate-binding site of the affinity gel is an alkoxide-bridged dinuclear zinc(II) complex, the 1,3-bis[bis(pyridin-2-ylmethyl)amino]propan-2-olato dizinc(II) complex (Phos-tag), which is linked to a highly cross-linked 4% (w/v) agarose. The affinity gel (Phos-tag agarose) was prepared by the quantitative reaction of N-hydroxysuccinimide-activated Sepharose and a Phos-tag derivative having a 2-aminoethylcarbamoyl group in dry CH3CN. Phosphopeptides were retrieved in a quantitative and highly selective manner by a spin column method using Phos-tag agarose at room temperature. Furthermore, in this study, we demonstrate a simple, rapid, and reusable affinity column chromatography for the separation of phosphorylated proteins such as ovalbumin, alpha(s1)-casein, and beta-casein at physiological pH. 相似文献
472.
[reaction: see text]. Upon treatment with lithiumorganic nucleophiles, trans-configured oxiranyl carbaldimines are transformed into anti-configured cis-aziridinyl alcohols with excellent diastereoselectivity. This conversion may be explained by a new type of the aza-Payne rearrangement, including first a nucleophilic attack on the imine carbon atom with diastereofacial differentiation followed by an intramolecular nucleophilic opening of the oxiranyl ring with simultaneous formation of the aziridine ring. 相似文献
473.
Two novel triterpenoid saponins, mimusopin ( 3-O-β-D-glucopyranosyl-2β, 3β, 6β, 23-tetrahydroxyolean-12-en-28-oic acid 28-O--L-rhamnopyranosyl-(1→3)-β-D-xylopyranosyl-(1→4)[a-L-rhamnopyranosyl-(1→ 3)]--L-rhamnopyranosyl-(1→2)--L-arabinopyranoside)(1) and mimusopsin 3-O-[β-D-glucopyranosyl-(1→3)β-D-gluco-pyranosyl]-2β, 3β, 6β, 23-tetrahydroxyolean-12-en-28-oic acid 28-O--L-rhamnopyranosyl-(1→3)-β-D-xylopyranosyl-(1→4)--L-rhamnopyranosyl-(1→2)--L-arabinopyranoside (2) were isolated from the seeds of Mimusops elengi. Their structures were elucidated by a combination of 2D-NMR (COSY, HOHAHA, HETCOR, HMBC and NOESY), FAB-MS/MS and strategic chemical degradation. In addition, molecular mechanics and dynamics studies showed that the lack of a 13C glycosylation shift at the C-4 of the inner rhamnose in 1 could be correlated with distortion in the corresponding torsion angles. 相似文献
474.
475.
José C. Barros Ricardo S. Yaunner Andréa Luzia F. de Souza Joaquim F. M. da Silva Octavio A. C. Antunes 《应用有机金属化学》2011,25(11):820-823
Sonogashira coupling of iodo‐ and bromoarenes and acetylenes using PdEnCat™ 30 in a phosphine‐, copper‐, amine‐, and microwave‐free system was developed, which allows for the preparation of a modulator of glutamate receptor mGluR5. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
476.
Namihira T. Tsukamoto S. Douyan Wang Katsuki S. Hackam R. Akiyama H. Uchida Y. Koike M. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》2000,28(2):434-442
Pulsed power has been used to remove nitric oxide (NO) in a mixture of nitrogen, oxygen, and water vapor simulating the flue gases from a power station stack. The effect of the pulsewidth at a fixed applied voltage on NO removal concentration was studied. The dependence of the energy efficiency of the removal of NO at a fixed applied voltage on the pulsewidth, on the removal ratio of NO and on the discharge current was investigated. This removal energy efficiency increases with decreasing pulsewidth and decreasing removal ratio of NO 相似文献
477.
Eri Matsuda Shin Tanaka Kenjiro Koike Aya Tanaka Makoto Sano Takanori Miyake 《Research on Chemical Intermediates》2008,34(5-7):535-549
Synthesis of an octahedral molecular sieve composed of Mn, Mg and O, known as todorokite, was studied in detail. The synthesis procedure is composed of three steps; layered birnessite synthesis, ion-exchange to buserite and final hydrothermal treatment of buserite. To obtain todorokites of different morphological properties, the aging time in the birnessite synthesis was varied. The effects of the aging time on properties of todorokites were studied by XRD, FE-SEM, TG-DTA, N2 adsorption-desorption, FT-IR and CO-TPD. In addition, catalytic activities of various todorokites for CO oxidation were investigated and the correlation between properties and activities was discussed. 相似文献
478.
T. Fukuchi T. Hori T. Masue K. Tajiri A. Sato T. Furukawa A. Odahara T. Shimoda Y. Wakabayashi Y. Gono T. Suzuki M. Ukai T. Wakui A. Yamazaki Y. Miyashita N. Sato M. Tateoka M. Ohguma T. Shinozuka T. Koike K. Shirotori Y. Miura S. Kinoshita Y. Ma Y. Y. Fu H. Tamura 《The European Physical Journal A - Hadrons and Nuclei》2009,39(1):49-51
The high-spin isomer in 151Er ( E x = 10.3 MeV, T 1/2 = 420 ns) has been studied by the 116Sn ( 40Ar , 5n) 151Er reaction at 197MeV. From the $ \gamma \gamma$ coincidence relations, a new transition with an energy of 1514keV was found. This finding requires the revision of the spin-parity assignment from previous 67/2- to 61/2+ or 65/2- . The 61/2+ assignment is the one which was predicted by the deformed independent particle model as an isomer with a large oblate deformation ( $ \beta$ = - 0.17) of the $\ensuremath[\nu(f_{7/2}h_{9/2} i_{13/2}) \pi(h^4_{11/2})]_{61/2^+}$ configuration. The isomerism may be attributed to the sudden shape change of the isomer from the nearly spherical shape of the lower-spin yrast states to the oblate shape. 相似文献
479.
New triterpenoid saponins from Maesa tenera. 总被引:2,自引:0,他引:2
Two new triterpenoid saponins, maetenosides A and B were isolated from the aerial parts of Maesa tenera and were respectively defined as 3-O-[beta-D-glucopyranosyl-(1-->2)-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-galactopyranosyl-(1-->3)][beta-D-glucopyranosyl-(1-->2)]-beta-D-glucuronopyranosyl camelliagenin A 22-O-angelate (1) and 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-galactopyranosyl-(1-->3)][beta-o-glucopyranosyl-(1-->2)]-beta-D-glucuronopyranosyl camelliagenin A 22-O-angelate (2). Their structures were established on the basis of chemical and spectroscopic methods. 相似文献
480.
Akira Sasaki Atsushi Sunahara Hiroyuki Furukawa Katsunobu Nishihara Takeshi Nishikawa Fumihiro Koike Hajime Tanuma 《High Energy Density Physics》2009,5(3):147-151
We present the development of population kinetics models for tin plasmas that can be employed to design an EUV source for microlithography. The atomic kinetic code is constrained for the requirement that the model must be able to calculate spectral emissivity and opacity that can be used in radiation hydrodynamic simulations. Methods to develop compact and reliable atomic model with an appropriate set of atomic states are discussed. Specifically, after investigation of model dependencies and comparison experiment, we improve the effect of configuration interaction and the treatment of satellite lines. Using the present atomic model we discuss the temperature and density dependencies of the emissivity, as well as conditions necessary to obtain high efficiency EUV power at λ = 13.5 nm. 相似文献