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11.
Ueno M Yonemoto M Hashimoto M Wheatley AE Naka H Kondo Y 《Chemical communications (Cambridge, England)》2007,(22):2264-2266
A novel type of deprotonative arylation of nucleophiles was conducted using Et(3)SiH/cat. t-Bu-P4 and the powerful S(N)Ar reactions of aryl fluorides were accomplished using alcohols and malonates as nucleophiles. 相似文献
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Andriani Furoida Misato Daitani Kyohei Hisano Osamu Tsutsumi 《Molecules (Basel, Switzerland)》2021,26(23)
Gold(I) complexes, enabling to form linear coordination geometry, are promising materials for manifesting both aggregation-induced emission (AIE) behavior due to strong intermolecular Au–Au (aurophilic) interactions and liquid crystalline (LC) nature depending on molecular geometry. In this study, we synthesized several gold(I) complexes with rod-like molecular skeletons where we employed a mesogenic biphenylethynyl ligand and an isocyanide ligand with flexible alkoxyl or alkyl chains. The AIE behavior and LC nature were investigated experimentally and computationally. All synthesized gold(I) complexes exhibited AIE properties and, in crystal, room-temperature phosphorescence (RTP) with a relatively high quantum yields of greater than 23% even in air. We have demonstrated that such strong RTP are drastically changed depending on the crystal-size and/or crystal growth process that changes quality of crystals as well as the aggregate structure, of e.g., Au–Au distance. Moreover, the complex with longer flexible chains showed LC nature where RTP can be observed. We expect these rod-like gold(I) complexes to have great potential in AIE-active LC phosphorescent applications such as linearly/circularly polarizing phosphorescence materials. 相似文献
13.
Hideto Tsuji Misato Nishikawa Yasushi Osanai Shuichi Matsumura 《Macromolecular rapid communications》2007,28(16):1651-1656
A novel preparation method for the core‐shell type biodegradable polyesters or biodegradable materials grafted with biodegradable polyesters was developed by alkaline surface treatment of biodegradable polyester films and subsequent enzymatic polymerization of aliphatic lactones, one example of which is shown in this study, i.e., the preparation of poly(L ‐lactide) (PLLA) film grafted with poly(ε‐caprolactone). It is revealed that only alkaline surface treatment or the combination of alkaline surface treatment and enzyme‐catalyzed grafting, the former and the latter, respectively accelerating and delaying the enzymatic degradation of PLLA, will give PLLA materials having a wide variety of biodegradability. Also, the specificity of the enzyme used for hydrolysis could be used to confirm the grafted chain species.
14.
Tatsuya Higashi Koichi Ito Misato Narushima Takahiro Sugiura Shinsuke Inagaki Jun Zhe Min Toshimasa Toyo'oka 《Biomedical chromatography : BMC》2011,25(11):1175-1180
A method for the quantification of progesterone (PROG) in human saliva using liquid chromatography–electrospray ionization–tandem mass spectrometry (LC‐ESI‐MS/MS) has been developed and validated. The saliva was deproteinized with acetonitrile, purified using a Strata™‐X cartridge, and subjected to LC‐ESI‐MS/MS. Quantification was based on selected reaction monitoring, and deuterated PROG was used as the internal standard. This method allowed the reproducible (intra‐ and inter‐assay relative standard deviations, <2.2%) and accurate (analytical recovery, 96.6–99.7%) quantification of the salivary PROG using a 400 μL sample, and the limit of quantification was 12.5 pg/mL. The developed method enabled detection of the variation in the salivary PROG concentrations of healthy volunteers during the menstrual cycle and measurement of the salivary concentrations of pregnant women. The method is expected to be an alternative to the blood PROG monitoring in clinical examinations, because saliva collection is easy, non‐invasive and repeatable. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Misato Kazama Hiroshi Shinotsuka Takashi Fujikawa Mauro Stener Piero Decleva Jun-ichi Adachi Tomoya Mizuno Akira Yagishita 《Journal of Electron Spectroscopy and Related Phenomena》2012
1s photoelectron angular distributions from fixed-in-space CO2, NO2, BF3 and CH3F molecules have been calculated by X-ray photoelectron diffraction (XPD) theory with muffin-tin-type molecular potential. For all the molecules, the calculated results show good agreements with those by density functional theory in the energy region ?100 eV. Furthermore, for all the molecules experimental data on the angular distributions in such energy region are well reproduced by the XPD theory. These intensive studies lead to a rather general rule that the XPD theory is an adequate tool to describe high-energy photoelectron angular distributions for any single oriented molecules. 相似文献
17.
Masaaki Suzuki Prof. Dr. Kengo Sumi Dr. Hiroko Koyama Dr. Siqin Takamitsu Hosoya Dr. Misato Takashima‐Hirano Hisashi Doi Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(45):12489-12495
The Pd0‐mediated rapid trapping of methyl iodide with an excess amount of a heteroaryl‐substituted tributylstannane has been investigated with the aim of incorporating a short‐lived 11C‐labelled methyl group into the heteroaromatic carbon frameworks of important organic compounds, such as drugs with various heteroaromatic structures, in order to execute a positron emission tomography (PET) study of vital systems. The reaction was first performed by using our previously developed CH3I/stannane/[Pd2(dba)3]/P(o‐CH3C6H4)3/CuCl/K2CO3 (1:40:0.5:2:2:2) system in DMF at 60 °C for 5 min (conditions A), however, the reaction gave low yields for various heteroaromatic compounds. Increasing the amount of phosphine ligand (conditions B) led to a significant improvement in the yield, but the conditions were still not suitable for a range of basic heteroaromatic structures. Use of the CuBr/CsF system (conditions C) also provided a result similar to that obtained under conditions B with an increased amount of the phosphine. Thus, pyridine and related heteroaromatic compounds remained less reactive substrates. The problem was overcome by replacing the DMF solvent with N‐methyl‐2‐pyrolidinone (NMP). The reaction in NMP at 60–100 °C for 5 min using a CH3I/stannane/[Pd2(dba)3]/P(o‐CH3C6H4)3/CuBr/CsF (1:40:0.5:16:2:5) combination (conditions D) gave the methylated products in yields of more than 80 % (based on the reaction of CH3I) for all of the heteroaromatic compounds listed in this study. Thus, the combined use of NMP and an increased amount of phosphine is important for promoting the reaction efficiently. The use of this general approach to rapid methylation has been well demonstrated by the synthesis of the PET tracers 2‐ and 3‐[11C]methylpyridines by using [Pd2(dba)3]/P(o‐CH3C6H4)3/CuBr/CsF (1:16:2:5) in NMP at 60 °C for 5 min, which gives the desired products in HPLC analytical yields of 88 and 91 %, respectively. 相似文献
18.
Daisuke Ishikawa Yuki Suzuki Chikako Kurokawa Masayuki Ohara Misato Tsuchiya Masamune Morita Miho Yanagisawa Masayuki Endo Ryuji Kawano Masahiro Takinoue 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(43):15443-15447
Bio‐inspired functional microcapsules have attracted increasing attention in many fields from physical/chemical science to artificial‐cell engineering. Although particle‐stabilised microcapsules are advantageous for their stability and functionalisation potential, versatile methods for their functionalisation are desired to expand their possibilities. This study reports a water‐in‐oil microdroplet stabilised with amphiphilic DNA origami nanoplates. By utilising DNA nanotechnology, DNA nanoplates were designed as a nanopore device for ion transportation and to stabilise the oil–water interface. Microscopic examination revealed the microcapsule formed by the accumulation of amphiphilic DNA nanoplates at the oil–water interface. Ion current measurements revealed the nanoplate pores functioned as channel to transport ions. These findings provide a general strategy for the programmable design of microcapsules to engineer artificial cells and molecular robots. 相似文献
19.
Kouki Matsubara Kiyoka Eda Yuki Ikutake Misato Dan Nao Tanizaki Yuji Koga Munehisa Yasuniwa 《Journal of polymer science. Part A, Polymer chemistry》2016,54(16):2536-2544
The homopolymerization reactions of several lactones, as well as the copolymerization reactions of DL‐lactide with these lactones were investigated using tridentate Schiff base aluminum complexes as the initiators. ε‐Caprolactone and δ‐valerolactone polymerized efficiently at room temperature to afford polyesters, whereas β‐butyrolactone only gave the corresponding oligomer. The copolymerization reactions of DL‐lactide with caprolactone and valerolactone yielded gradient block copolymers where the lactyl blocks formed crystalline stereoblocks as a consequence of the stereoselective polymerization of DL‐lactide in the presence of the aluminum complexes. These polymerization processes were highly controlled in nature, and block copolymerization where caprolactone copolymerized using poly(DL‐lactide)‐Al complex proceeded. The obtained gradient copolymer containing stereoblock lactyl blocks and caproyl blocks were analyzed using WAXD analysis to uncover existence of the crystalline stereoblock lactyl blocks in the copolymer. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2536–2544 相似文献
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Erika Toki Shiori Osaki Misato Nakamura Kazuki Tsuoka Nobutoshi Samejima Tetsuto Nakashima Rin Abe Takahiro Oyama Koichi Tsukiyama 《国际化学动力学杂志》2020,52(12):907-917
We conducted a simultaneous measurement of the potential of Cu2+, oxidation-reduction potential (ORP), and the chemiluminescence intensity in the luminol-H2O2-KSCN-CuSO4-NaOH system. Two types of chemiluminescence were identified: a very faint continuous chemiluminescence and a strong oscillating chemiluminescence. The correlation between the potential of Cu2+ and ORP was measured experimentally for the first time. The effect of the initial concentrations of Cu2+ and H2O2 on the overall chemiluminescence intensity and the oscillation frequency was investigated in detail. Time-dependent concentration variation of the chemical species existing in the reaction system was calculated using a Runge-Kutta method. Two elementary chemical reactions not considered previously were taken into consideration. The overall experimental behavior was well explainable with our simulation. Based upon the comparison of our simulation with the experiment, we proposed that the strong oscillating chemiluminescence was induced by the reaction of luminol with ·OS(O)CN. 相似文献