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981.
Shigeo Suzuki Rika Tanaka Keiko Takada Nozomi Inoue Yuka Yashima Akiko Honda Susumu Honda 《Journal of chromatography. A》2001,910(2):115
A method for the analysis of the sialo-N-glycans in glycoproteins was established by the electrokinetic chromatography mode of capillary electrophoresis (CE) in sodium dodecyl sulfate (SDS) micelles as 1-phenyl-3-methyl-5-pyrazolone (PMP) derivatives, using sialo-N-glycans in fetuin as a model. Six major and some minor peaks were observed for the N-glycans in fetuin, which were well separated from each other using 50 mM phosphate buffer, pH 6.0, containing SDS to a concentration of 30 mM in an uncoated fused-silica capillary, and these peaks were assigned to sialo-N-glycans having either of the biantennary or β1-3/β1-4 linked galactose-containing complex type triantennary N-glycans as the basic structures, by an indirect method based on the assignment of the peaks in high-performance liquid chromatography separated in parallel with CE and peak collation between these two separation methods. The attaching position of the sialic acid residue was determined using the linkage preference of neuraminidase isozymes. The established system is considered to be useful for routine analysis of microheterogeneity of the carbohydrate moiety of this model glycoprotein from the following reasons: (1) the derivatization with PMP proceeds quantitatively under mild conditions without causing release of the sialic acid residue, (2) the derivatives can be sensitively detected by UV absorption, (3) the procedure is simple, rapid and reproducible. Preliminary results of N-glycan analysis for several other glycoproteins under these conditions are also presented. 相似文献
982.
983.
984.
Prof. Dr. Takashi Uemura Ryo Nakanishi Shuto Mochizuki Prof. Dr. Susumu Kitagawa Prof. Dr. Motohiro Mizuno 《Angewandte Chemie (International ed. in English)》2016,55(22):6443-6447
The radical polymerization of vinyl monomers was performed in a tetrahedral imine‐linked organic cage with extrinsic porosity (CC3). Because of its dynamic and responsive packing structure, CC3 endowed the polymerization with specific behaviors. The adsorption of styrene triggered a change in the CC3 assembly, resulting in a monomer arrangement that was suitable for polymerization within the host matrix. The polymerization reaction was strongly dependent on the crystallinity of CC3 and was promoted by amorphization of the host in a cooperative manner, which is not possible with conventional rigid porous materials. Furthermore, CC3 can recognize the polarity of substrates, and thus polar monomers, such as methyl methacrylate and acrylonitrile, could not induce the structural changes in CC3 that are required for polymerization. This monomer specificity governed by the flexibility of CC3 is useful to the prevent incorporation of unfavorable monomers into the polymeric products. 相似文献
985.
Boron Difluoride Complexes of Expanded N‐Confused Calix[n]phyrins That Demonstrate Unique Luminescent and Lasing Properties 下载免费PDF全文
Dr. Masatoshi Ishida Toshihiro Omagari Ryuji Hirosawa Keisuke Jono Dr. Young Mo Sung Dr. Yuhsuke Yasutake Prof. Dr. Hidemitsu Uno Dr. Motoki Toganoh Prof. Dr. Hajime Nakanotani Prof. Dr. Susumu Fukatsu Prof. Dr. Dongho Kim Prof. Dr. Hiroyuki Furuta 《Angewandte Chemie (International ed. in English)》2016,55(39):12045-12049
Complexation of novel multiply N‐confused expanded calix[n]phyrins with boron difluoride afforded a new class of cyclic BODIPY (boron‐dipyrromethene) arrays. The structures of circularly arranged BODIPY subunits linked in an N‐confused fashion give rise to such photophysical properties unique to the macrocycles as redshifted emission wavelengths along with apparent large Stokes shifts, long emission lifetimes, and solid‐state lasing. The DFT calculations support the size‐dependent excited‐state dynamics of the macrocycles. 相似文献
986.
Dr. Keisuke Kishida Dr. Yoshikuni Okumura Yoshihiro Watanabe Megumi Mukoyoshi Dr. Silvia Bracco Prof. Angiolina Comotti Prof. Piero Sozzani Dr. Satoshi Horike Prof. Susumu Kitagawa 《Angewandte Chemie (International ed. in English)》2016,55(44):13784-13788
The separation of 1,3‐butadiene from C4 hydrocarbon mixtures is imperative for the production of synthetic rubbers, and there is a need for a more economical separation method, such as a pressure swing adsorption process. With regard to adsorbents that enable C4 gas separation, [Zn(NO2ip)(dpe)]n (SD‐65; NO2ip=5‐nitroisophthalate, dpe=1,2‐di(4‐pyridyl)ethylene) is a promising porous material because of its structural flexibility and restricted voids, which provide unique guest‐responsive accommodation. The 1,3‐butadiene‐selective sorption profile of SD‐65 was elucidated by adsorption isotherms, in situ PXRD, and SSNMR studies and was further investigated by multigas separation and adsorption–desorption‐cycle experiments for its application to separation technology. 相似文献
987.
Dr. Ryo Ohtani Dr. Munehiro Inukai Dr. Yuh Hijikata Dr. Tetsuya Ogawa Dr. Mikihito Takenaka Prof. Masaaki Ohba Prof. Susumu Kitagawa 《Angewandte Chemie (International ed. in English)》2015,54(4):1139-1143
Novel organic–inorganic hybrid liposomes, so‐called coordination polymersomes (CPsomes), with artificial domains that exhibit strong lateral cohesion were prepared by a three‐step procedure that formed a coordinative interaction leading to a lipid bilayer. First, the lipophilic complex (dabco‐C18)[Mn(N)(CN)4(dabco‐C18)] ( 1 ; dabco‐C18+=1,4‐diazabicyclo[2,2,2]octane‐(CH2)17? CH3 cation), was synthesized. 1 has a lipophilic alkyl tail part and a tetracyanometallate head group, which can be used for an expansion to two‐dimensional coordination networks. Second, 1 and 1,2‐dipalmitoyl‐sn‐glycero‐3‐phosphocholine were mixed to prepare the liposomes. Finally, CPsomes were obtained by the addition of transition‐metal ions ( M ) to form unilamellar faceted liposomes with plain CP raft domains with Mn? CN? M linkages. The concentration of 1 influences the size of the CP raft domains and the shape of the CPsomes. The synthesis of coordination polymers in lipid bilayers is a novel approach for the construction of artificial architectures as raft domains, for example, in cell membranes. 相似文献
988.
Dr. Lok Kumar Shrestha Dr. Rekha Goswami Shrestha Prof. Yusuke Yamauchi Dr. Jonathan P. Hill Dr. Toshiyuki Nishimura Prof. Kun'ichi Miyazawa Prof. Takazumi Kawai Prof. Susumu Okada Dr. Katsunori Wakabayashi Prof. Katsuhiko Ariga 《Angewandte Chemie (International ed. in English)》2015,54(3):951-955
Here we report the thermal conversion of one‐dimensional (1D) fullerene (C60) single‐crystal nanorods and nanotubes to nanoporous carbon materials with retention of the initial 1D morphology. The 1D C60 crystals are heated directly at very high temperature (up to 2000 °C) in vacuum, yielding a new family of nanoporous carbons having π‐electron conjugation within the sp2‐carbon robust frameworks. These new nanoporous carbon materials show excellent electrochemical capacitance and superior sensing properties for aromatic compounds compared to commercial activated carbons. 相似文献
989.
Formation of Foam‐like Microstructural Carbon Material by Carbonization of Porous Coordination Polymers through a Ligand‐Assisted Foaming Process 下载免费PDF全文
Dr. Kanokwan Kongpatpanich Dr. Satoshi Horike Yu‐ichi Fujiwara Naoki Ogiwara Dr. Hirotomo Nishihara Prof.Dr. Susumu Kitagawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(38):13278-13283
Porous carbon material with a foam‐like microstructure has been synthesized by direct carbonization of porous coordination polymer (PCP). In situ generation of foaming agents by chemical reactions of ligands in PCP during carbonization provides a simple way to create lightweight carbon material with a foam‐like microstructure. Among several substituents investigated, the nitro group has been shown to be the key to obtain the unique foam‐like microstructure, which is due to the fast kinetics of gas evolution during carbonization. Foam‐like microstructural carbon materials showed higher pore volume and specific capacitance compared to a microporous carbon. 相似文献
990.
Ikuo Ueta Yohei Nakamura Koji Fujimura Susumu Kawakubo Yoshihiro Saito 《Chromatographia》2017,80(1):151-156
Gaseous formic acid (FA) and acetic acid (AA) were concentrated by a needle-type extraction device, and the extracted analytes were determined using a gas chromatography-barrier discharge ionization detector. An activated carbon particle showed good extraction/desorption performance for FA and AA. The limit of quantification for FA and AA was 900 and 180 ng L?1 at sample volumes of 100 mL, and 150 and 30 ng L?1 at a sample volume of 600 mL, respectively. The storage performance of the analytes in the extraction needle was quantitatively evaluated at different temperatures, and the applicability of the proposed method to determine FA and AA in air samples was demonstrated. 相似文献