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211.
Kamagata K Kawaguchi T Iwahashi Y Baba A Fujimoto K Komatsuzaki T Sambongi Y Goto Y Takahashi S 《Journal of the American Chemical Society》2012,134(28):11525-11532
A method was developed to detect fluorescence intensity signals from single molecules diffusing freely in a capillary cell. A unique optical system based on a spherical mirror was designed to enable quantitative detection of the fluorescence intensity. Furthermore, "flow-and-stop" control of the sample can extend the observation time of single molecules to several seconds, which is more than 1000 times longer than the observation time available using a typical confocal method. We used this method to scrutinize the fluorescence time series of the labeled cytochrome c in the unfolded state. Time series analyses of the trajectories based on local equilibrium state analysis revealed dynamically differing substates on a millisecond time scale. This system presents a new avenue for experimental characterization of the protein-folding energy landscape. 相似文献
212.
213.
Kamada K Hara C Ogawa K Ohta K Kobuke Y 《Chemical communications (Cambridge, England)》2012,48(64):7988-7990
The two-photon absorption properties of a self-organized dimer of a free-base and zinc(II) porphyrins tandem linked with an ethynylene group and terminated by imidazolyl and phenylethynyl groups were investigated. The self-organized dimer was found to exhibit strong two-photon absorption and furthermore the saturation of the two-photon absorption owing to the intense transition. 相似文献
214.
Imamura K Hashimoto K Kominami H 《Chemical communications (Cambridge, England)》2012,48(36):4356-4358
m-Nitrovinylbenzene was chemoselectively reduced to m-aminovinylbenzene in a suspension of a TiO(2) photocatalyst in the presence of a hole scavenger at room temperature under atmospheric pressure without the use of a precious metal or reducing gas, and nitrobenzenes having other reducible groups were also chemoselectively reduced to corresponding aminobenzenes. 相似文献
215.
Terao J Kimura K Seki S Fujihara T Tsuji Y 《Chemical communications (Cambridge, England)》2012,48(10):1577-1579
We developed a new method for the synthesis of an organic-soluble insulated molecular wire (IMW) with permethylated cyclodextrin (PMCD); this method involves click polymerization of linked [2]rotaxane containing azide and alkynyl groups at both ends of a π-conjugated guest. 相似文献
216.
T Nohara A Imamura M Yamaguchi KI Hidari T Suzuki T Komori H Ando H Ishida M Kiso 《Molecules (Basel, Switzerland)》2012,17(8):9590-9620
A novel ganglioside bearing Neua2-3Gal and Neua2-6Gal structures as distal sequences was designed as a ligand for influenza A viruses. The efficient synthesis of the designed ganglioside was accomplished by employing the cassette coupling approach as a key reaction, which was executed between the non-reducing end of the oligosaccharide and the cyclic glucosylceramide moiety. Examination of its binding activity to influenza A viruses revealed that the new ligand is recognized by Neua2-3 and 2-6 type viruses. 相似文献
217.
T Mizuhara S Oishi H Ohno K Shimura M Matsuoka N Fujii 《Organic & biomolecular chemistry》2012,10(33):6792-6802
3,4-Dihydro-2H,6H-pyrimido[1,2-c][1,3]benzothiazin-6-imine (PD 404182) is a virucidal heterocyclic compound active against various viruses, including HCV, HIV, and simian immunodeficiency virus. Using facile synthetic approaches that we developed for the synthesis of pyrimido[1,2-c][1,3]benzothiazin-6-imines and related tricyclic derivatives, the parallel structural optimizations of the central 1,3-thiazin-2-imine core, the benzene part, and the cyclic amidine part of PD 404182 were investigated. Replacement of the 6-6-6 pyrimido[1,2-c][1,3]benzothiazin-6-imine framework with 5-6-6 or 6-6-5 derivatives led to a significant loss of anti-HIV activity, and introduction of a hydrophobic group at the 9- or 10-positions improved the potency. In addition, we demonstrated that the PD 404182 derivative exerts anti-HIV effects at an early stage of viral infection. 相似文献
218.
Photoluminescence and magnetic circular dichroism of the IrQ(ppy)2-5Cl compound were investigated between 15 and 295 K. These results have been compared with the output files obtained from Density Functional Theory by using the Gaussian 03W software and some additional packages. The experimental results confirm the first triplet state absorption which arises from d to πQ transition. The temperature dependence photoluminescence have shown a small interaction with the polystyrene, used for dispersion of IrQ(ppy)2-5Cl compound. The green and red phosphorescence have the same temperature dependence. The MCD spectra, especially at 15 K, reveals the main transitions involved in the Metal-to-Ligand Charge Transfer processes from the Ir towards the two ligands, phenylpyridine and quinoline, respectively. 相似文献
219.
Gen Tanaka Ikuhiko Nakase Yasunori Fukuda Ryo Masuda Shinya Oishi Kazuya Shimura Yoshimasa Kawaguchi Tomoka Takatani-Nakase Ülo Langel Astrid Gräslund Katsuya Okawa Masao Matsuoka Nobutaka Fujii Yasumaru Hatanaka Shiroh Futaki 《Chemistry & biology》2012,19(11):1437-1446
Highlights? CXCR4 was identified as a receptor to stimulate cellular uptake of R12 peptide ? Interaction with R12 stimulates internalization of CXCR4 via macropinocytosis ? SDF-1α and HIV-1 gp120 protein also induce macropinocytosis ? Macropinocytic uptake of HIV-1 diminished the infection of host cells 相似文献
220.
Akane Sato Mizuho Okada Kazuya Saito Michio Sorai 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):564-565
In the crystal structure of the title charge‐transfer complex, namely trans‐stilbene–2,2′‐(2,3,5,6‐tetrafluorobenzene‐1,4‐diylidene)propanedinitrile (1/1) (trans‐STB–TCNQF4), C14H12·C12F4N4, the planar STB and TCNQF4 molecules are stacked alternately. The structure is not isostructural with that of STB–TCNQ. No anomaly was found in the displacement parameters of any atoms, while the bond length of the central C=C moiety was shorter than the corresponding bond in ethylene. This suggests that the central C=C moiety of the STB molecule vibrates with a large amplitude, similar to the case in free STB and STB–TCNQ. 相似文献