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991.
T Yoshioka Y Aizawa T Fujita K Nakamura K Sasahara H Kuwano T Kinoshita H Horikoshi 《Chemical & pharmaceutical bulletin》1991,39(8):2124-2125
The glucuronide of a new oral antidiabetic agent, (+/-)-5-[4-(6-hydroxy-2,5,7,8-tetramethylchroman-2-yl- methoxy)benzyl]thiazolidine-2,4-dione (CS-045) (1), was synthesized to confirm the structure of a metabolite in monkeys (Macaca fascicularis) and to examine its antidiabetic activity. The glucuronide also had antidiabetic activity in KK-mice. 相似文献
992.
Takahiro Kuroda Yoshimasa Sakurai Yukinao Suzuki AkikoO. Nakamura Masayasu Kuwahara Hiroaki Ozaki Hiroaki Sawai 《化学:亚洲杂志》2006,1(4):575-580
Branched tris‐DNA, in which two oligonucleotides of the same sequence and one other oligonucleotide of a different sequence are connected with a rigid central linker, was prepared chemically by using a DNA synthesizer. Two branched tris‐DNA molecules with complementary DNA sequences form dimer and tetramer as well as linear and spherical oligomer complexes. The complex formation was studied by UV/thermal denaturation, enzyme digestion, gel electrophoresis, and AFM imaging. 相似文献
993.
Yao M Iwamura Y Inoue H Yoshioka N 《Langmuir : the ACS journal of surfaces and colloids》2005,21(2):595-601
Five amphiphilic meso-disubstituted porphyrins bearing one polar group were synthesized, and their monolayer films were prepared. Their limiting molecular areas obtained from pi-A isotherms were 0.5-0.6 nm2, which were smaller than those of the corresponding meso-tetrasubstituted porphyrins. At the air-water interface, the disubstituted porphyrins showed a broad band in visible absorption spectra compared with the solution state, and the red shift of the Soret band exhibited a significant dependence on the kind of hydrophilic groups at the meso positions. Interestingly, the monolayer of the disubstituted porphyrin bearing a carboxyphenyl group (1-CO2H) showed a blue shift of the Soret band by adding cadmium chloride to the subphase, and the spectra varied upon multilayer deposition. The observed phenomena were interpreted by using the exciton theory. The effect of hydrophilic substituents on the absorption spectra of disubstituted porphyrin monolayers is discussed. 相似文献
994.
Shinsuke Yamanaka Hiroaki Muta Shin-ichi Kobayashi 《Journal of solid state chemistry》2004,177(10):3484-3489
Polycrystalline samples of strontium series perovskite type oxides, SrHfO3 and SrRuO3 were prepared and the thermophysical properties were measured. The average linear thermal expansion coefficients are 1.13×10−5 K−1 for SrHfO3 and 1.03×10−5 K−1 for SrRuO3 in the temperature range between 423 and 1073 K. The melting temperatures Tm of SrHfO3 and SrRuO3 are 3200 and 2575 K, respectively. The longitudinal and shear sound velocities were measured by an ultrasonic pulse-echo method at room temperature in air, which enables to evaluate the elastic moduli and Debye temperature. The heat capacity was measured by using a differential scanning calorimeter, DSC in high-purity argon atmosphere. The thermal diffusivity was measured by a laser flash method in vacuum. The thermal conductivities of SrHfO3 and SrRuO3 at room temperature are 5.20 and 5.97 W m−1 K−1, respectively. 相似文献
995.
Biogenetic-type synthesis of (±)-dictyopterene A () was achieved employing 1,-5-undecadien-3-ol () postulated to be a biosynthetic intermediate of : this synthesis means that transformation of dictyoprolene () into dictyopterene A () was formally made. 相似文献
996.
A theory of the coupled random walk (CRW) process which has been proposed by one of the present authors, is developed further. It is shown that the Fokker-Planck equation obtained from the CRW process can be cast into a form of a kinetic equation similar to the Boltzmann equation of the gas theory. To this end, the memory effects are taken into account through the jumping probabilities between the modes. As a special case, the distribution function for the steady state is considered. 相似文献
997.
Selective Dinitrogen Conversion to Ammonia Using Water and Visible Light through Plasmon‐induced Charge Separation 下载免费PDF全文
Dr. Tomoya Oshikiri Prof. Kosei Ueno Prof. Hiroaki Misawa 《Angewandte Chemie (International ed. in English)》2016,55(12):3942-3946
The generation of ammonia from atmospheric nitrogen and water using sunlight is a preferable approach to obtaining ammonia as an energy carrier and potentially represents a new paradigm for achieving a low‐carbon and sustainable‐energy society. Herein, we report the selective conversion of dinitrogen into ammonia through plasmon‐induced charge separation by using a strontium titanate (SrTiO3) photoelectrode loaded with gold nanoparticles (Au‐NPs) and a zirconium/zirconium oxide (Zr/ZrOx) thin film. We observed the simultaneous stoichiometric production of ammonia and oxygen from nitrogen and water under visible‐light irradiation. 相似文献
998.
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
999.
Sato Y Yoshioka K Tanaka M Murakami T Ishida MN Niwa O 《Chemical communications (Cambridge, England)》2008,(40):4909-4911
Densely packed co-adsorbed ultrathin mono molecular layers of short tri(ethylene glycol)-alkanethiolate (for repelling proteins) and maltoside terminated alkanethiolate (for capturing lectin) provided an extremely high signal to noise ratio surface: the repelling molecules, which had two different functions (highly flexible-hydrophilic arm and rigid packing tail group), worked as "nano barriers" in the recognition monolayer. 相似文献
1000.
Shimizu M Katsuda N Katsurada T Mitani M Yoshioka Y 《The journal of physical chemistry. B》2008,112(47):15116-15126
The molecular and electronic structures of the Rieske iron-sulfur [2Fe-2S] cluster with an imidazolate and imidazole were investigated by using usual unrestricted and broken symmetry B3LYP methods for the highest and lowest spin states, respectively. The electronic structures of the lowest spin states were determined by the spin contaminations and natural orbital analyses. It was shown that the spin contamination presents the number of pairs of the antiferromagnetic spin couplings. The oxidation mechanism of the ubquinol at the Q(p) site of the cytochrome bc(1) complex was also examined by the broken symmetry B3LYP methods. In the [2Fe-2S] clusters with an imidazolate, the oxidized and lowest spin state, [(Imz(-))FeS](ox)LS, was lowest in energy among four possible states, consistent with experimental observations. In the examination of the mechanism of the ubquinol oxidation, it was confirmed that the ubiquinol docks between the imidazolate of [2Fe-2S] clusters and Glu272(-) of cytochrome b by the hydrogen bonds before the oxidation proceeds, consistent with the experimental proposals. Our results support a "Glu272-first" mechanism that Glu272 serves as an acceptor of the first proton from the ubiquinol and subsequently the proton-coupled electron transfer (PCET) occurs from the ubisemiquinone anion to the Rieske iron-sulfur [2Fe-2S] cluster. 相似文献