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Naoki Taka Hiroshi Koga Haruhiko Sato Takenori Ishizawa Tadakatsu Takahashi 《合成通讯》2013,43(23):4263-4269
The novel potassium channel openers benzopyran-4-amides have been synthesized via palladium-catalyzed amidation of 4-bromobenzopyrans under an atmoshere in the presence of an equivalent of potassium iodide. 相似文献
13.
Prof. Dr. Manabu Yamada Fumiya Uemura Dr. Uma Maheswara Rao Kunda Prof. Dr. Takenori Tanno Prof. Dr. Hiroshi Katagiri Prof. Dr. Fumio Hamada 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(38):8393-8399
Alkanes composed of C−C and C−H show a low electric polarization, and therefore, there is only very weak interaction between alkanes and adsorbents. Thus, it is difficult to separate a specific alkane from a mixture of alkanes by adsorption. Here, two activated “channel-like” crystals generated from brominated thiacalix[4]arene propyl ethers, which adopt 1,3-alternate and partial cone conformations, recognize specific alkane vapors depending on alkane-shape and -size, sorting in three-type alkane guests such as linear, branched, and cyclic alkanes. Two activated crystals, which are prepared by removal of solvent upon heating under reduced pressure, incorporate branched and/or cyclic alkane vapors by a unique “gate-opening” mechanism via a crystal transformation in the process. Linear alkane vapors do not trigger gate opening and are not taken up by the activated crystals. The shape and size molecular-recognition properties of the activated crystals promises considerable usefulness for the separation of linear, branched, and cyclic alkanes. 相似文献
14.
An Isotope‐Coded Fluorogenic Cross‐Linker for High‐Performance Target Identification Based on Photoaffinity Labeling
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Dr. Takenori Tomohiro Shota Morimoto Toshiya Shima Dr. Junya Chiba Dr. Yasumaru Hatanaka 《Angewandte Chemie (International ed. in English)》2014,53(49):13502-13505
A photoaffinity labeling (PAL)‐based method for the rapid identification of target proteins is presented in which a high‐performance chemical tag, an isotope‐coded fluorescent tag (IsoFT), can be attached to the interacting site by irradiation. Labeled peptides can be easily distinguished among numerous proteolytic digests by sequential detection with highly sensitive fluorescence spectroscopy and mass spectrometry. Subsequent MS/MS analysis provides amino acid sequence information with a higher depth of coverage. The combination of PAL and heterogeneous target‐selecting techniques significantly reduces the amount of time and protein required for identification. An additional photocleavable moiety successfully accelerated proteomic analysis using cell lysate. This method is a widely applicable approach for the rapid and accurate identification of interacting proteins. 相似文献
15.
Ryota Kudo Masahiro Sonobe Yoshiaki Chino Yu Kitazawa Mutsumi Kimura 《Molecules (Basel, Switzerland)》2020,25(23)
The synthesis and characterization of two phthalocyanine (Pc) structural isomers, 1 and 2, in which four 2,6-di(hexyloxy)phenyl units were attached directly to the 1,8,15,22- or 1,4,15,18-positions of the Pc rings, are described. Both Pcs 1 and 2 exhibited low melting points, i.e., 120 and 130 °C respectively, due to the reduction in intermolecular π-π interaction among the Pc rings caused by the steric hindrance of 2,6-dihexyloxybenzene units. The thermal behaviors were investigated with temperature-controlled polarizing optical microscopy, differential scanning calorimetry, powder X-ray diffraction, and absorption spectral analyses. Pc 1, having C4h molecular symmetry, organized into a lamellar structure containing lateral assemblies of Pc rings. In contrast, the other Pc 2 revealed the formation of metastable crystalline phases, including disordered stacks of Pcs due to rapid cooling from a melted liquid. 相似文献
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The kinetics of the flattening of surface corrugations of float glasses were investigated in dry nitrogen at 610 to 670°C. The amplitude of the sinusoidal surface profile decayed exponentially with time while its wavelength remained constant. The dependence of decay rate on wavelength indicated that the process is controlled by the viscous flow. From the obtained rate constant the viscosity was calculated using the surface energy value determined independently by the zero-creep method. The viscosity thus obtained reflects the mass transport property in the vicinity of the glass surface. It was several times larger than that determined by the fibre elongation or intrusion method which should reflect the bulk properties. No difference in the decay rate was observed on both the surfaces of float glass of which only one side had been exposed to molten tin during the glass manufacturing process. 相似文献
18.
Suwa Y Matsuura S Fujimori M Heike S Onogi T Kajiyama H Hitosugi T Kitazawa K Uda T Hashizume T 《Physical review letters》2003,90(15):156101
Novel atomic structures on a H-terminated Si(100)-(2x1)-H surface were found using scanning tunneling microscopy (STM). The structures are distinguishable only from Si dimers in empty-state STM images. They were observed on arsenic- and phosphorus-doped substrates, but not on boron-doped substrates. Surface density of these structures was found to be proportional to the dopant density in the substrate. First-principles calculations clarify that they are consisting of dopant pairs that are segregated from the bulk material. Hydrogen atoms attached to the dopant pair are found to flip between two positions on the surface due to a quantum effect. 相似文献
19.
Isao Ohta Ichiro Hagino Takenori Kaneko 《International Journal of Infrared and Millimeter Waves》1989,10(6):729-735
Two different types of 5/2-wavelength rat-race-type directional couplers with a remarkably increased power-split ratio for a realizable ring-impedance, in particular which are useful for millimeter-wave circuits suffering from the severe restriction on the usable impedance range, are described. Experimental corroboration is provided in the microwave region (at 8 GHz). 相似文献
20.
Takenori Mitamura 《Tetrahedron letters》2010,51(27):3538-3194
Upon treatment of a mixture of alkynyl selenides and acetylenedicarboxylates with Pd(OAc)2/P(o-tol)3/K2CO3/H2O-catalytic system, the alkynylselenation of acetylenedicarboxylates takes place to give the corresponding alkynylvinyl selenides. Furthermore, alkynyl selenides undergo the intermolecular [2+2+2] cycloaddition reaction in the presence of PdCl2(PPh3)2 as a catalyst, affording the corresponding multisubstituted aryl selenides selectively. 相似文献