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81.
82.
K. Kikunaga T. Yamamoto Y. Tanaka N. Kikuchi K. Tokiwa T. Watanabe N. Terada 《Physica C: Superconductivity and its Applications》2010,470(21):1916-1919
(Cu, C)–Ba–O thin films have been deposited at low growth temperature of 450–570 °C by pulsed laser deposition method. A control of CO2 gas pressure and the growth temperature, usage of BaCuyOx pellet target resulted in an expansion of twice c-axis length of BaCuO2 structure (2c phase) and a significant rise of conductivity. Measurements of in-situ XPS suggest that the 2c phase should be (Cu, C)Ba2CuOx [(Cu, C)-1201]. The maximum temperature of onset of the superconducting transition and zero resistance state obtained so far were 60 and 47 K, respectively. 相似文献
83.
84.
A large variety of α-selenoglycosides, including alkyl and aryl selenoglycosides, selenoglycosyl amino acid and selenodisaccharide have been synthesized in a stereoselective manner. The key precursor of α-anomeric selenolate anion was designed as p-methylbenzoyl selenoglycoside, which was synthesized by the reaction of β-glycosyl chloride with potassium p-methylselenobenzoate. Upon the action of piperazine or methylhydrazine in the presence of Cs2CO3, the acyl selenoglycoside produced an anomeric selenolate anion, which reacted in situ with various electrophilic counterparts to yield α-selenoglycoside. 相似文献
85.
We developed fluorescent probes (1 and 2) based on the structure of cis-p-coumaroylagmatine (3), a leaf-opening substance of Albizzia julibrissin Durazz. These probes were effective for the leaf-opening of A. julibrissin, and specifically bind to the motor cell of this plant. Moreover, binding of the fluorescent probe was specific to the plant motor cell contained in the plants belonging to the Albizzia genus. These results showed that the binding of a probe compound with a motor cell is specific to the plant genus and suggested that the genus-specific receptor molecule for the leaf-movement factor on a motor cell would be involved in nyctinasty. 相似文献
86.
Takahiro Ikazaki Dr. Eri Ishikawa Hiroto Tamashima Dr. Hisako Akiyama Dr. Yusuke Kimuro Dr. Makoto Yoritate Dr. Hiroaki Matoba Prof. Dr. Akihiro Imamura Prof. Dr. Hideharu Ishida Prof. Dr. Sho Yamasaki Prof. Dr. Go Hirai 《Angewandte Chemie (International ed. in English)》2023,62(22):e202302569
Glycoconjugate analogues in which the sp3-hybridized C2 position of the carbohydrate structure (normally bearing a hydroxy group) is converted into a compact sp2-hybridized exomethylene group are expected to have unique biological activities. We established ligand-controlled Tsuji–Trost-type glycosylation methodology to directly prepare a variety of these 2-exomethylene pseudo-glycoconjugates, including glucosylceramide analogues, in an α- or β-selective manner. Glucocerebrosidase GBA1 cleaves these synthetic pseudo-β-glucosylceramides similarly to native glucosylceramides. The pseudo-glucosylceramides exhibit selective ligand activity towards macrophage-inducible C-type lectin (Mincle), but unlike native glucosylceramides, are inactive towards CD1d. 相似文献
87.
Kazuhiro Nakabayashi Mizuki Takata Masaki Furukawa Hideharu Mori 《Journal of polymer science. Part A, Polymer chemistry》2020,58(6):852-859
Luminescent core–shell nanoparticles (NPs) with crosslinked aggregation-induced emission (AIE) core structures, which exhibited excellent emission independent of the dispersion state of the NPs, have been developed by a facile one-pot method based on the self-assembly of an amphiphilic block copolymer poly(PEGMA)-b-poly(DB3VT). Core–shell micelles with a poly(DB3VT) core were formed from poly(PEGMA)-b-poly(DB3VT) in tetrahydrofuran (THF)/H2O condition, and the crosslinked AIE-based structure was selectively incorporated into the core by the Suzuki coupling reaction between poly(DB3VT) blocks and tetraphenylethylene (TPE)-based coupling monomers at the same time. This method afforded a uniform NP with a crosslinked TPE-based AIE core structure. The obtained NP exhibited excellent emission both in diluted solution and solid states. This result indicated that the formed TPE-based AIE core structure was always aggregated regardless of NP dispersion owing to the crosslinking as we expected. The crosslinked TPE-based AIE core structure, which was related to the emission property, was readily tuned by the selection and combination of coupling monomers in the Suzuki coupling reaction. By incorporating electron-deficient units into the core, the emission color could be successfully tuned from yellow-green to orange and red while maintaining the emission property independent of the state of the NP dispersion. These results demonstrated that NPs with the crosslinked AIE core structures are a promising luminescent material design motif to realize emission independent on molecular dispersion. 相似文献
88.
Sekiguchi A Nishina A Kimura H Fukumoto RH Kanoh K Ishihara H Koketsu M 《Chemical & pharmaceutical bulletin》2005,53(11):1439-1442
We investigated the superoxide anion scavenging effects of thirteen 2-amino-1,3-selenazoles using a highly sensitive quantitative chemiluminescence method. At 166 microM, the 2-amino-1,3-selenazoles scavenged in the range of 14.3 to 96.7% of O2-. 2-Piperidino-1,3-selenazole and 4-phenyl-2-piperidino-1,3-selenazole exhibited the strongest superoxide anion-scavenging activity among the 2-amino-1,3-selenazoles. The 50% inhibitory concentrations (IC50) of 2-piperidino-1,3-selenazole and 4-phenyl-2-piperidino-1,3-selenazole were determined to be 4.03 microM and 92.6 microM, respectively. Thus, these compounds acted in vitro as effective O2- scavengers. 相似文献
89.
We propose and demonstrate a new scheme of high-efficiency generation of the three-photon polarization-entangled W state, which is a typical three-qubit entangled state. The high efficiency has enabled the first full characterization of the state by quantum state tomography. We have analyzed the obtained state and observed its nature of tripartite entanglement and robustness of entanglement. 相似文献
90.
Mikio Hoshino Reiko Konishi Hideharu Seto Hiroshi Seki Hirotaka Sonoki Takashi Yokoyama Hiroshi Shimamori 《Research on Chemical Intermediates》2001,27(1-2):189-204
Photolysis of dibenzoyldiazene gives benzoyl radicals. In aerated solutions, the benzoyl radicals react with oxygen to yield benzoylperoxy radicals. Spin trapping studies indicate that 5,5′dimethyl-1-pyrroline N-oxide reacts with the benzoylperoxy radicals to produce the adduct which exhibits ESR parameters, AN = 13.8 G and AHβ = 10.1 G. Laser photolysis studies reveal that the rate constants for the reaction between the benzoyl radical and oxygen are ca. 4 × 109 M-1 s-1 in toluene, acetone, and ethyl acetate. The benzoylperoxy radicals undergo one-electron oxidation of tetramethyl-p-phenylenediamine, TMPD, to give an ion pair. The ion pair has an absorption spectrum similar to that of the TMPD cation radical. The formation of the ion pair is detected by monitoring the absorbance change at 600 nm after laser pulsing. From the kinetic studies for the formation of the ion pair in the presence of olefins, the bimolecular rate constants for reactions between several olefins and the benzoylperoxy radical are determined. The electrophilic addition of the benzoylperoxy radicals to olefins is discussed in comparison with the addition reactions of thiyl radicals to olefins. The detection and determination of the dipole moments of both the benzoylperoxy radicals and the ion pair are carried out with the use of the time-resolved microwave dielectric absorption technique. The distance between the positive and negative ions in the ion pair is estimated as 0.20 nm. 相似文献