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971.
Asymmetric epoxidation of α-substituted acroleins with hydrogen peroxide has been catalyzed by diphenylprolinol diphenylmethylsilyl ether to afford α-substituted-β,β-unsubstituted-α,β-epoxy aldehyde with excellent enantioselectivity and the generation of a chiral quaternary carbon center. The method was applied to a short synthesis of (R)-methyl palmoxirate. 相似文献
972.
Naoya Takahashi Yuji Takahara Daisuke Ishikawa Norio Matsuki Yuji Ikegaya 《Analytical and bioanalytical chemistry》2010,398(1):211-218
Functional multineuron calcium imaging (fMCI) is a large-scale technique used to access brain function on a single-neuron
scale. It detects the activity of individual neurons by imaging action potential-evoked transient calcium influxes into their
cell bodies. fMCI has recently been used as a high-throughput research tool to examine how neuronal activity is altered in
animal models of brain diseases, for example stroke, Alzheimer’s disease, and epilepsy, and to estimate how pharmacological
agents act on normal and abnormal states of neuronal networks. It offers unique opportunities to discover the mechanisms underlying
neurological disorders and new therapeutic targets. 相似文献
973.
Ishikawa T 《Chemical & pharmaceutical bulletin》2010,58(12):1555-1564
Guanidines are categorized as strong organobases; however, their catalytic utility in organic synthesis has not been discussed thoroughly. The author's group has extensively and systematically studied their potential ability focusing on: 1) modified guanidines as chiral auxiliaries; 2) guanidinium ylides for aziridine formation; 3) the affinity of bisguanidine for proton and metal salts; and 4) the potential chirality of bisguanidine. Under the first topic, a variety of chiral guanidines was designed by the introduction of chirality on the three guanidinyl nitrogens, and the modified guanidines prepared using our original methods were found to be effective not only in catalytic but also in stoichiometric asymmetric syntheses. Under the second topic, the reaction of guanidinium salts carrying a glycinate function with aromatic or unsaturated aldehydes under basic conditions unexpectedly afforded aziridine-2-carboxylates, which were available as useful building blocks in organic synthesis due to their convertibility to functionalized amino acid derivatives in the ring-opening reaction, together with urea compounds recyclable to the starting guanidinium salts. The introduction of a chiral template to the guanidinium salt allowed us to expand the cyclic aziridination reaction to an asymmetric version. Under the third topic, effective complexabilty of bisguanidines with either proton or metal ions in water was observed, suggesting their possible application to the removal of toxic substances from polluted water and recovery of rare elements as material sources. Under the final topic, monomethylation or monoethylation of bisguanidine afforded a chiral product via asymmetric crystallization, indicating that bisguanidines have a potential chiral character due to the plane asymmetry. 相似文献
974.
975.
976.
Yasutaka Omori Shinji Tokonami Tetsuo Ishikawa Sarata Kumar Sahoo Naofumi Akata Atsuyuki Sorimachi Masahiro Hosoda Chanis Pornnumpa Paitoon Wanabongse Hiromi Kudo Ye-Jing Hu Yong-Xiang Ao Xiao-Liang Li Kun Li Ying-Hua Fu Quan-Fu Sun Suminori Akiba 《Journal of Radioanalytical and Nuclear Chemistry》2015,306(1):317-323
977.
978.
The infrared and Raman spectra of Cd(15NH3)2Cl2 are reported and a comparison is made between the normal and 2H isotope substituted compounds. A further refinement of the Local Symmetry Force Constants was carried out. 相似文献
979.
Mutsunori Uenuma Bin Zheng Takanori Imazawa Masahiro Horita Takashi Nishida Yasuaki Ishikawa Heiji Watanabe Ichiro Yamashita Yukiharu Uraoka 《Applied Surface Science》2012,258(8):3410-3414
The metal-induced lateral crystallization (MILC) of an amorphous Ge (a-Ge) thin film using Ni nanoparticles (NPs) was investigated. Ni-NPs were formed and evenly distributed onto a 30 nm thick a-Ge film by cage-shaped protein. After complete elimination of protein shell, crystal growth was performed at 400 °C. Raman spectra and electron backscatter diffraction (EBSD) studies revealed that a poly-Ge film with a maximum grain size approximately 1 μm was successfully formed. The Ni contamination in the poly-Ge film was reduced by more than one order of magnitude compared with that in the case of a conventional MILC process. 相似文献
980.
Alexei N. Grum-Grzhimailo Tatiana Pikuz Anatoly Faenov Takeshi Matsuoka Norimasa Ozaki Bruno Albertazzi Sergei Pikuz Yuichi Inubushi Makina Yabashi Kensuke Tono Hirokatsu Yumoto Haruhiko Ohashi Tetsuya Ishikawa Ryosuke Kodama 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2017,71(3):69