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371.
Kazunari Tsuboike 《Tetrahedron》2004,60(34):7367-7374
Synthesis of an aziridinomitosene core structure that relies on a facile tertiary-amine base-catalyzed azide conjugate addition is reported. Straightforward derivatization of the conjugate addition product affords the desired mitomycin ring system. Initial catalyst screens have identified peptides that afford the product with modest enantioselectivities. 相似文献
372.
Yoshihiro Shimoyama Dr. Tomoya Ishizuka Dr. Hiroaki Kotani Prof. Dr. Yoshihito Shiota Prof. Dr. Kazunari Yoshizawa Dr. Kaoru Mieda Prof. Dr. Takashi Ogura Dr. Toshihiro Okajima Prof. Dr. Shunsuke Nozawa Prof. Dr. Takahiko Kojima 《Angewandte Chemie (International ed. in English)》2016,55(45):14041-14045
Proton‐coupled electron‐transfer oxidation of a RuII?OH2 complex, having an N‐heterocyclic carbene ligand, gives a RuIII?O. species, which has an electronically equivalent structure of the RuIV=O species, in an acidic aqueous solution. The RuIII?O. complex was characterized by spectroscopic methods and DFT calculations. The oxidation state of the Ru center was shown to be close to +3; the Ru?O bond showed a lower‐energy Raman scattering at 732 cm?1 and the Ru?O bond length was estimated to be 1.77(1) Å. The RuIII?O. complex exhibits high reactivity in substrate oxidation under catalytic conditions; particularly, benzaldehyde and the derivatives are oxidized to the corresponding benzoic acid through C?H abstraction from the formyl group by the RuIII?O. complex bearing a strong radical character as the active species. 相似文献
373.
A Photoelectrochemical Solar Cell Consisting of a Cadmium Sulfide Photoanode and a Ruthenium–2,2′‐Bipyridine Redox Shuttle in a Non‐aqueous Electrolyte
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Yosuke Kageshima Hiromu Kumagai Tsutomu Minegishi Prof. Jun Kubota Prof. Kazunari Domen 《Angewandte Chemie (International ed. in English)》2015,54(27):7877-7881
A photoelectrochemical (PEC) cell consisting of an n‐type CdS single‐crystal electrode and a Pt counter electrode with the ruthenium–2,2′‐bipyridine complex [Ru(bpy)3]2+/3+ as the redox shuttle in a non‐aqueous electrolyte was studied to obtain a higher open‐circuit voltage (VOC) than the onset voltage for water splitting. A VOC of 1.48 V and a short‐circuit current (ISC) of 3.88 mA cm?2 were obtained under irradiation by a 300 W Xe lamp with 420–800 nm visible light. This relatively high voltage was presumably due to the difference between the Fermi level of photo‐irradiated n‐type CdS and the redox potential of the Ru complex at the Pt electrode. The smooth redox reaction of the Ru complex with one‐electron transfer was thought to have contributed to the high VOC and ISC. The obtained VOC was more than the onset voltage of water electrolysis for hydrogen and oxygen generation, suggesting prospects for application in water electrolysis. 相似文献
374.
375.
Sopis Chuekachang Rapiphun Janmanee Akira Baba Sukon Phanichphant Saengrawee Sriwichai Kazunari Shinbo Keizo Kato Futao Kaneko Nobuko Fukuda Hirobumi Ushijima 《Surface and interface analysis : SIA》2013,45(11-12):1661-1666
In this study, we present an electrochemically controlled surface plasmon resonance (EC‐SPR) biosensor to detect adrenaline on poly(2‐aminobenzylamine) (P2ABA) thin films. The P2ABA thin films are stable and display electroactivity in a neutral PBS solution. Specific detection of adrenaline was performed on P2ABA thin films because the benzylamine groups in the P2ABA structure could specifically react with adrenalines. Adrenaline was detected in real time by EC‐SPR spectroscopy, which provides an EC‐SPR reflectivity change on the P2ABA thin film upon adrenaline injection. The measured responses were quite different from those for uric acid and ascorbic acid, which are major interferences in adrenaline detection. The electrochemically applied potential facilitates the specific detection of adrenaline. In addition, the detection of adrenaline on the P2ABA thin films was investigated by a quartz crystal microbalance technique. The detection limit for adrenaline at open circuit potential was 10 pM. The present study provides a useful information on the detection of adrenaline on the P2ABA thin films. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
376.
377.
378.
N. Nogawa S. Momose K. Miyazawa Y. Makide K. Oohashi K. Hashimoto N. Morikawa 《Journal of Radioanalytical and Nuclear Chemistry》1999,239(2):385-389
Optimum conditions were determined for high-yield synthesis of186Re- and188Re-meso-2, 3-dimercaptosuccinic acid complexes applicable to animal injection. The yield was more than 95% under the conditions
used. The bone accumulation of the complexes was remarkable in the biodistributions in mice. 相似文献
379.
H. Momose N. Mori C. Hamaguchi T. Ikaida H. Arimoto N. Miura 《Physica E: Low-dimensional Systems and Nanostructures》1999,4(4):286
We present a review on recent study of the type I to type II transition in short-period superlattices (SLs) of GaAs/AlAs by means of cyclotron resonance (CR) in pulsed high magnetic fields. The behavior of CR varies depending on the thickness of the GaAs and AlAs layers. In CR of (GaAs)n/(AlAs)n, the resonance peak at the X minima was observed in the type II regime for n smaller than 14, whereas the resonance at the Γ point was observed for n>15. We estimated electron masses on X and Γ point in the SLs by using the empirical sp3 tight-binding method including second-nearest-neighbor interaction. These calculations have shown good agreement with the experimental results. Moreover, it was found that the angular dependence of the CR peak position does not obey the simple cosine dependence due to the subband mixing in high magnetic fields. From the angular dependence in the SLs, the longitudinal and transverses electron masses of AlAs at the X point were deduced to be mt=0.21m0 and ml=1.04m0, respectively. 相似文献
380.
Kazunari Naka Hirofumi Sato Akihiro Morita Fumio Hirata Shigeki Kato 《Theoretical chemistry accounts》1999,102(1-6):165-169
The free-energy profile for the Menshutkin-type reaction NH3 + CH3Cl → NH3CH3
+ + Cl− in aqueous solution is studied using the RISM-SCF method. The effect of electron correlation on the free-energy profile is
estimated by the RISM-MP2 method at the HF optimized geometries along the reaction coordinate. Solvation was found to have
a large influence on the vibrational frequencies at the reactant, transition state and product; these vibrational frequencies
are utilized to calculate the zero-point energy correction of the free-energy profile. The computed barrier height and reaction
exothermicity are in reasonable agreement with those of experiment and previous calculations. The change of solvation structure
along the reaction path is represented by radial distribution functions between solute-solvent atomic sites. The mechanisms
of the reaction are discussed from the view points of solute electronic and solvation structures.
Received: 26 June 1998/Accepted: 28 August 1998 / Published online: 2 November 1998 相似文献