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排序方式: 共有920条查询结果,搜索用时 31 毫秒
71.
72.
Ryoma Masuda Yuuya Kawasaki Kazunobu Igawa Yoshiyuki Manabe Hiroshi Fujii Nobuo Kato Katsuhiko Tomooka Junko Ohkanda 《化学:亚洲杂志》2020,15(6):742-747
Mid‐sized molecules have emerged as an attractive chemical space and potentially provide a robust basis for the development of synthetic agents to control intracellular protein interactions. However, the limited cell permeability and chemical tractability of such agents remain to be addressed. We envisioned that target‐templated synthesis of such mid‐sized molecules might provide a solution. Here, we exploited a copper‐free Huisgen cycloaddition for template synthesis using a peptide fragment containing a 4,8‐diazacyclononyne (DACN) moiety and an azide‐containing fusicoccin derivative in the presence or absence of recombinant 14‐3‐3ζ protein in vitro. Time‐course changes in the yield of products demonstrated that the reaction was accelerated in the presence of 14‐3‐3 and one of the regioisomers was generated predominantly, supporting the template effect. 相似文献
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74.
Hirofusa Shirai Kenji Hanabusa Toshiki Koyama Hisanaga Tsuiki Etsuko Masuda 《Macromolecular Symposia》1992,59(1):155-162
The oxidation of HO-CH2-CH2-SH (RSH) by molecular oxygen and Fe(III)- as well as Co(II)-multicarboxyphthalocyanine and the mechanism in homogeneous aqueous system were investigated. As application to enzyme-like heterogeneous catalysts, Fe(III)-as well as Co(II)-octacarboxyphthalocyanine were supported on amorphous enriched rayon staple fiber and their enzyme-like activities were estimated. These fibers were applicated to new odor-removers acting as artificial enzyme systems. 相似文献
75.
Ali Z. Al-Rubaie Sakae Uemura Hideki Masuda 《Journal of organometallic chemistry》1991,410(3):309-320
A new tellurium-containing heterocyclic compound, 2,2,6,6-tetramethyl-1-oxa-4-tellura-2,6-disilacyclohexane (C6H16OSi2Te) (1), has been prepared by treatment of 1,3-bis(chloromethyl)-1,1,3,3-tetramethyldisiloxane with sodium telluride. Mononuclear and dinuclear palladium complexes of this telluride have been prepared by the reaction of 1 with PdCl2(PhCN)2 and Na2PdCl4, respectively. The following new derivatives of 1 have also been produced: C6H16OSi2TeI2 (2), C6H16OSi2TeBr2, C6H16OSi2TeCl2, C6H16OSi2Te(CH3)I, and C6H16OSi2Te(CH2Ph)Br. IR, 1H and 13C NMR and mass spectral data of these new compounds are reported and discussed. 1H NMR studies revealed that in CDCl3 solution both telluronium salts reductively eliminate alkyl halide. The crystal structure of compound 2 has been determined by X-ray diffraction. The compound crystallizes in the monoclinic space group, P21/c, with four molecules in a unit cell of dimension a 12.960(3), b 8.846(2), c 13.754(4) Å, β 92.44(2)°, R = 0.049, and Rw = 0.067 for 3599 unique reflections with |F0| > 3σ(F0). The compound forms a six-membered ring of a slightly displaced boat type. The geometry about the Te atom is pseudo-octahedral, with two carbon atoms (Te-C = 2.156(7) and 2.137(6) Å) and two iodine atoms of the neighbouring molecules (weak intermolecular bonds, Te · I = 3.769 and 3.806 Å) in the equatorial positions and two iodine atoms (Te-I = 2.909(1) and 2.913(1) Å) in the axial positions. 相似文献
76.
The isotope ratios of molybdenum in molybdenites were studied. A special triple filament technique was used to obtain stable and lasting signals for MO+ . There are no differences bigger than ±0.4 parts per IO4 among four samples and the standard. 相似文献
77.
78.
Jun Koyanagi Keita Takeguchi Kazuki Murai Hirokazu Furue Nobuyuki Masuda 《Molecular Crystals and Liquid Crystals》2017,656(1):54-65
Blue-phase liquid crystals form three-dimensional structures in a self-organizing manner and are similar to living tissue structures such as the teeth of mice and collagen tissues. This study presents numerical results regarding the conditions under which blue-phase liquid crystals occur. The Monte Carlo simulations are performed by employing an improved Lennard–Jones potential that considers anisotropy and chirality. The conditions for the formation of the blue phase, which vary with respect to the chirality, are examined first. The relationship between the anisotropic parameters and the chiral parameter for the formation of the blue phase is discussed. Identical blue-phase structures are obtained, even when the cell size and molecular number are varied drastically. This discussion is useful for considering the scale-up problem, which is almost always a difficult issue for molecular-scale simulations. 相似文献
79.
Yuya Nakatsuji Prof. Dr. Yusuke Kobayashi Sakyo Masuda Prof. Dr. Yoshiji Takemoto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(8):2633-2637
Organo-radical catalysts have recently attracted great interest, and the development of this field can be expected to broaden the applications of organocatalysis. Herein, the first example of a radical-generating system is reported that does not require any photoirradiation, radical initiators, or preactivated substrates. The oxidative C−C-bond cleavage of 2-substituted cyclohexanones was achieved using an azolium salt and a hydroquinone as co-catalysts. A catalytic mechanism was proposed based on the results of diffusion-ordered spectroscopy and cyclic voltammetry measurements, as well as computational studies. 相似文献
80.