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[reaction: see text] Aryl ketones were reduced to the corresponding alcohols with excellent enantioselectivity (up to 99.7% ee) by Cl3SiH in the presence of a catalytic amount of N-formyl-alpha'-(2,4,6-triethylphenyl)-L-proline as an activator. Both carboxyl group at the alpha-position of the activator and 2,4,6-triethylphenyl group at the alpha'-position were critical for the high enantioselectivity. 相似文献
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Masakazu Yoshikawa Kanako Murakoshi Kana Hanaoka Gilles P. Robertson 《European Polymer Journal》2006,42(10):2532-2539
Novel polymeric materials, having a chiral environment, were obtained by the reaction of lithiated polysulfone with chiral terpenoid myrtenal. The resulting polymers gave self-standing durable membranes. Molecularly imprinted membranes were prepared from the novel myrtenal-containing polysulfones by the presence of print molecules during the membrane preparation process. The d-isomer imprinted membrane showed d-isomer adsorption and diffusivity selectivity, and vice versa. As a result, the d-isomer imprinted membrane transported the d-isomer in preference to the l-isomer, and vice versa. The control non-imprinted membrane also showed permselectivity toward racemic glutamic acid mixtures. The expression of permselectivity for the molecularly imprinted membranes was synergistically due to adsorption and diffusivity selectivity. 相似文献
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Niidome T Nakashima K Takahashi H Niidome Y 《Chemical communications (Cambridge, England)》2004,(17):1978-1979
Cationic gold nanoparticles, prepared by reducing HAuCl(4) with NaBH(4) in the presence of 2-aminoethanethiol, formed a complex with plasmid DNA, and could be transfected into cultivated cells. 相似文献
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Ono S Ogawa K Yamashita K Yamamoto T Kazuta Y Matsuda A Shuto S 《Chemical & pharmaceutical bulletin》2002,50(7):966-968
(1S,2R)-1-phenyl-2-[(S)-1-aminopropyl]-N,N-diethylcyclopropanecarboxamide (2b, PPDC), a new class of potent N-methyl-D-aspartic acid (NMDA) receptor antagonist, was designed based on a new method for restricting the conformation of compounds having a cyclopropane ring. The three-dimensional structures of PPDC obtained by the three different methods of X-ray crystallographic analysis, usual MM2-calculations in vacuum, and MM2 calculations based on the nuclear Overhauser effect (NOE) data in D2O are similar, which are in accord with that hypothesized. These results suggest that this conformational restriction method is particularly effective in designing novel biologically active molecules. 相似文献
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Dr. Kanako Nakamae Prof. Takayuki Nakajima Prof. Yasuyuki Ura Prof. Yasutaka Kitagawa Prof. Tomoaki Tanase 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(6):2282-2287
By using a linear tetraphosphine, meso-bis[(diphenylphosphinomethyl)phenylphosphino]methane (dpmppm), nona- and hexadecanuclear copper hydride clusters, [Cu9H7(μ-dpmppm)3]X2 (X=Cl ( 1 a ), Br ( 1 b ), I ( 1 c ), PF6 ( 1 d )) and [Cu16H14(μ-dpmppm)4]X2 (X2=I2 ( 2 c ), (4/3) PF6⋅(2/3) OH ( 2 d )) were synthesized and characterized. They form copper-hydride cages of apex-truncated supertetrahedral {Cu9H7}2+ and square-face-capped cuboctahedral {Cu16H14}2+ structures. The hydride positions were estimated by DFT calculations to be facially dispersed around the copper frameworks. A kinetically controlled synthesis gave an unsymmetrical Cu8H6 cluster, [Cu8H6(μ-dpmppm)3]2+ ( 3 ), which readily reacted with CO2 to afford linear Cu4 complexes with formate bridges, leading to an unprecedented hydrogenation of CO2 into formate catalyzed by {Cu4(μ-dpmppm)2} platform. The results demonstrate that new motifs of copper hydride clusters could be established by the tetraphosphine ligands, and the structures influence their reactivity. 相似文献
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Kayoko Minakata Hideki Nozawa Itaru Yamagishi Kunio Gonmori Masako Suzuki Koutaro Hasegawa Amin Wurita Kanako Watanabe Osamu Suzuki 《Analytical and bioanalytical chemistry》2014,406(5):1331-1338
A rapid determination method is presented for gold (Au3+) and platinum (Pt4+) in tissues using matrix-assisted laser desorption ionization quadrupole time-of-flight mass spectrometry (MALDI-Q-TOF-MS). Au and Pt ions in wet-ashed tissue solution were reacted with diethyldithiocarbamate (DDC), and the resulting chelate complex ions Au(DDC)2 + and Pt(DDC)3 + were detected by MALDI-Q-TOF-MS using α-cyano-4-hydroxycinnamic acid as a matrix. The limit of detection (LOD) was 0.8 ng/g tissue and the quantification range was 2–400 ng/g for Au, and the LOD was 6 ng/g tissue and the quantification range was 20–4,000 ng/g for Pt. The Pt levels detected by MALDI-Q-TOF-MS in several tissues of a patient overdosed with cisplatin were nearly the same as those detected by flow-injection electrospray ionization mass spectrometry. The LODs of Au and Pt were 0.04 pg per well (sample spot) and 0.3 pg per well, respectively. To our knowledge, this is the first attempt to quantify Au3+ and Pt4+ ions in tissues by MALDI-Q-TOF-MS.
A rapid determination method is presented for gold and platinum in tissues using matrix-assisted laser desorption ionization quadrupole time-of-flight mass spectrometry (MALDI-Q-TOF-MS). Au and Pt ions in wet-ashed tissue solution were reacted with diethyldithiocarbamate (DDC), and the resulted chelate complex ions Au(DDC)2 + and Pt(DDC)3 + were detected using α-cyano-4-hydroxycinnamic acid as a matrix. 相似文献