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671.
Tomoaki Anabuki Keisuke Ohashi Taichi E. Takasuka Hideyuki Matsuura Kosaku Takahashi 《Molecules (Basel, Switzerland)》2022,27(1)
Abscisic acid (ABA, 1) is a plant hormone that regulates various plant physiological processes such as seed developing and stress responses. The ABA signaling system has been elucidated; binding of ABA with PYL proteins triggers ABA signaling. We have previously reported a new method to isolate a protein targeted with a bioactive small molecule using a biotin linker with alkyne and amino groups, a protein cross-linker, and a bioactive small molecule with an azido group (azido probe). This method was used to identify the unknown ABA binding protein of Arabidopsis thaliana. As a result, AtTrxh3, a thioredoxin, was isolated as an ABA binding protein. Our developed method can be applied to the identification of binding proteins of bioactive compounds. 相似文献
672.
Akitomo Tachibana Susumu Kawauchi Koichi Nakamura Hideyuki Inaba 《International journal of quantum chemistry》1996,57(4):673-682
Three isoelectronic reactions, proton transfer (PT ), hydrogen abstraction (HA ), and electron transfer (ET ), of NH+3 with NH,3 H2O, and HF have been studied using ab initio molecular orbital calculations. For the reaction of NH+3 + H2O, the energy of the transition state (TS) is higher than that of the reactants. This is consistent with the experimental observation that the rate constant is less than the average dipole orientation (ADO) rate constant. It seems reasonable that the reaction rate for the reaction NH+3 + H2O would hardly depend on the v2 mode of NH+3 at least for low-lying excited states (Eint≤ 0.714 eV) of the v2 mode, because the v2 mode contributes mainly to the normal mode orthogonal to the reaction coordinate at the TS . This is consistent with experimental observation. A similar prediction can be made for the NH+3 + HF reaction. The electron-transfer processes for the HA reactions have been examined in terms of the intrinsic reaction coordinate (IRC ). The order of reactivity with NH+3 is NH3 > H2O > HF. It is found that the degree of the electron transfer and the reactivity are correlated with the absolute hardness (η) of NH3, H2O, and HF. This is in accord with the softness as the chemical reactivity index in the density functional theory. © 1996 John Wiley & Sons, Inc. 相似文献
673.
Masayori Fujioka Hideyuki Okada Yukihiko Kusaka Satoko Nishiyama Hiromichi Noguchi Shigeru Ishii Yasuhiko Yoshida 《Macromolecular rapid communications》2004,25(20):1776-1780
Summary: The title polymers, in which both the stem and the graft are biodegradable, have been synthesized for the first time in a one‐pot, lipase‐catalyzed, graft‐polymerization reaction (in bulk, at 70 °C) of β‐butyrolactone (β‐BL) and ε‐caprolactone (ε‐CL) onto chitin and chitosan. The reactivity order of the lactones was found to be ε‐CL > β‐BL ≫ γ‐BL (no reaction). All the graft polymers prepared are insoluble in common organic solvents.
674.
The chemo- and stereoselective glycosidations of sulfinylglycosides and alcohols using a heteropoly acid, H3PW12O40, as a new promoter have been developed. 相似文献
675.
Liu Zhenlin Ohtake Hideyuki Izumida Shinji Ono Shingo Sarukura Nobuhiko 《Optical and Quantum Electronics》2000,32(4-5):521-529
The THz-radiation power from InAs reaches sub-mW level in a 1.7-T magnetic field irradiated with femtosecond laser pulses of 1.5-W average power. The THz-radiation power is related almost quadratically both to the magnetic field and to the excitation laser power. Furthermore, the THz-radiation spectrum is found to be controlled by the excitation pulsewidth, chirp direction of the excitation pulse, and the magnetic field. 相似文献
676.
Norio Kashiwa Shin-ichi Kojoh Nobuo Kawahara Shingo Matsuo Hideyuki Kaneko Tomoaki Matsugi 《Macromolecular Symposia》2003,201(1):319-326
This paper describes a new synthetic route for polyolefinic graft block copolymers by adopting coupling reaction between terminally hydroxylated polyolefins and maleic anhydride grafted polyolefins. Terminally hydroxylated polypropylene (PP-OH) was coupled with maleic anhydride modified polyethylene (PE-g-MAH) and such ethylene-propylene random copolymer (EPR-g-MAH) to give polyolefinic graft block copolymers (PE-g-PP and EPR-g-PP, respectively). The formation of PE-g-PP was confirmed by enhancement on molecular weight and it brought about distinctive decrease in size of dispersed domain in its phase separation morphology. Occurrence of coupling reaction to give EPR-g-PP was indicated by extreme decrease in its solubility to n-decane and it led to unique morphology demonstrating lamella microstructure that had never been reported for a comparable polyolefin composite. 相似文献
677.
678.
Jun-ichi Kadokawa Hideyuki Habu Shinji Fukamachi Masa Karasu Hideyuki Tagaya Koji Chiba 《Macromolecular rapid communications》1998,19(12):657-660
This communication describes the direct polycondensation of carbon dioxide with p- and m-xylylene glycols using the system trisubstituted phosphine/carbon tetrahalide/base as a condensing agent. The polymerization reaction of carbon dioxide with p-xylylene glycol was carried out in the presence of the condensing agent in N,N-dimethylformamide. The yield was at most 81.0% obtained by using the condensing agent tributylphosphine/carbon tetrabromide/N-cyclohexyl-N′,N′,N″,N″-tetramethylguanidine (CyTMG). The structure of the product was determined by means of 1H NMR, 13C NMR, and IR spectroscopy to be that of a polycarbonate. The molecular weight was estimated to be ca. 1 000–2 000 by 1H NMR analyses. 相似文献
679.
Luminescent species observed in the polyolefins were mainly foreign impurities, i.e., polynuclear aromatics (PNA) adsorbed from an ambient atmosphere. The luminescent species adsorbed under normal atmospheric conditions and an equivalent amount of PNA did not affect the photodegradation of high-density polyethylene (HDPE). On the other hand, the extracted precipitates from HDPE accelerated the photodegradation of the polymer and, also, 3-octanone slightly accelerated it, but little effect was observed in 1-icosene. Therefore, the activity of impurities on the photodegradation of HDPE can be expressed in the following order: Extracted precipitates >> C=sO > PNA ∞ -CH=CH2 相似文献
680.
Takuma Watabe Prof. Hideyuki Otsuka 《Angewandte Chemie (International ed. in English)》2023,62(9):e202216469
We report a novel and versatile approach to achieving swelling-induced mechanochemistry using a multinetwork (MN) strategy that enables polymer networks to repeatedly swell with monomers and solvents. The isotropic expansion of the first network (FN) provides sufficient force to drive the mechanochemical scission of a radical-based mechanophore, difluorenylsuccinonitrile (DFSN). Although prompt recombination generally occurs in such highly mobile environments, the resulting pink radicals are kinetically stabilized in the gels, probably due to limited diffusion in the extended polymer chains. Moreover, the DFSN embedded in the isotropically strained chain exhibits increased thermal reactivity, which can be reasonably explained by an entropic contribution of the FN to the dissociation. The utility of the MN polymers is demonstrated not only in terms of swelling-force-induced network modification, but also in the context of tunable reactivity of the dissociative unit through proper design of the hierarchical network architecture. 相似文献