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101.
The title compound was prepared by two different procedures. The first route starts with acetonitrile-d3 and goes through 2-trideuteriomethyl-5-nitroimidazole ( 6 ) (Scheme I). The second and more convenient process is direct labeling of metronidazole ( 1 ) with alkaline ethanol-d1. 相似文献
102.
Noriyoshi Kon Nobuhiko Iki Yusuke Yamane Shin Shirasaki Sotaro Miyano 《Tetrahedron letters》2004,45(1):207-211
2,14-Dithiacalix[4]arene 34 was conveniently prepared in 16% yield by acid-catalyzed cyclocondensation of 2,2′-thiobis[4-tert-butylphenol] with formaldehyde. The present method also afforded the first isolation of the analogues with six and eight phenol units, 36 (10%) and 38 (5%), respectively. Solvent extraction showed that 34 had high selectivity toward Cu2+ ion at pH 5.5 by coordination of the bridging sulfur with cooperative donation of the adjacent phenolate oxygens. 相似文献
103.
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
104.
105.
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
106.
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
107.
This paper reports on a procedure for photoviscoelastic analysis where the axes of principal stress, principal strain and polarization of light coincide in the presence of a large temperature change. More specially, the transient-thermal stress and strain due to stress in an epoxy beam subjected to quenching from both the upper and lower surfaces, are determined using the time-temperature-equivalent law for stress, strain and birefringence. The transient-thermal stress and strain in the beam were determined experimentally using hereditary integrations from the measurement of the transient temperature and birefringence due to the quenching of the beam. The transient thermal stress and strain were also calculated theoretically using the linear-viscoelastic theory. The experimentally determined thermal stress agrees closely with the theoretical results. The experimentally determined strain agrees qualitatively with the theoretical values. Thus, it is concluded that the photoviscoelastic technique is useful in analyzing the proposed problem.Paper was presented at 1982 SESA/JSME Spring Meeting held in Maui and Oahu, HI on May 23–28, 1982. 相似文献
108.
109.
Kazuyuki Kubota Toshimi Mizukoshi Hiroshi Miyano 《Analytical and bioanalytical chemistry》2013,405(25):8093-8103
Here, we describe a novel method for l-phenylalanine analysis using a sandwich-type immunometric assay approach for use as a new method for amino acid analysis. To overcome difficulties of the preparation of high-affinity and selectivity monoclonal antibodies against l-phenylalanine and the inability to use sandwich-type immunometric assays due to their small molecular weight, three procedures were examined. First, amino groups of l-phenylalanine were modified by “N-Fmoc-l-cysteine” (FC) residues and the derivative (FC-Phe) was used as a hapten. Immunization of mice with bovine serum albumin/FC-Phe conjugate successfully yielded specific monoclonal anti-FC-Phe antibodies. Second, a new derivatization reagent, “biotin linker conjugate of FC-Phe N-succinimidyl ester” (FC(Biotin)-NHS), was synthesized to convert l-phenylalanine to FC-(Biotin)-Phe as a hapten structure. The biotin moiety linked to the thiol group of cysteine formed a second binding site for streptavidin/horseradish peroxidase (HRP) conjugates for optical detection. Third, a new semi-sandwich-type immunometric assay was established using pre-derivatized l-phenylalanine, the monoclonal anti-FC-Phe antibody, and streptavidin/HRP conjugate (without second antibody). Using the new “semi-sandwich” immunometric assay system, a detection limit of 35 nM (60 amol per analysis) and a detection range of 0.1–20 μM were attained using a standard l-phenylalanine solution. Rat plasma samples were analyzed to test reliability. Intra-day assay precision was within 6 % of the coefficient of variation; inter-day variation was 0.1 %. The recovery rates were from 92.4 to 123.7 %. This is the first report of the quantitative determination of l-phenylalanine using a reliable semi-sandwich immunometric assay approach and will be applicable to the quantitative determination of other amino acids. 相似文献
110.
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