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91.
[reaction: see text] The reaction of heteroaromatic compounds with propargylic carboxylates in the presence of a catalytic amount of [RuCl(2)(CO)(3)](2) or PtCl(2) gives trienes in good yields. The key intermediate is an electrophilic (1-acetoxylvinyl)carbene complex generated from the activated propargylic acetates with transition metals. 相似文献
92.
Bandyopadhyay A Nittoh K Wakayama Y Yagi S Miki K 《The journal of physical chemistry. B》2006,110(42):20852-20857
We have applied simultaneous horizontal and vertical bias to a single molecule (2 nm(2)) in an ordered and disordered matrix to virtually isolate and tune its property without taking it out physically from its environment. Using a dedicated electrode system, we have locally tuned nanoscale properties vertically by STM, while stabilizing its environment by applying a global electric field horizontally. Using this technique, we report tuning of molecular conformations in room temperature, whose evolution of states has been statistically investigated. We have also shown control on switching of a few selected conformations by applying dual bias simultaneously. As we avoid any direct injection of charge into the system via electrode contact, this technique could be used as a generalized method to tune phenomena evolved in an environment of weak interaction from a large distance without destroying the property. 相似文献
93.
K. Miki A. Tamii N. Aoi T. Fukui T. Hashimoto K. Hatanaka T. Ito T. Kawabata H. Matsubara K. Ogata H. J. Ong H. Sakaguchi S. Sakaguchi T. Suzuki J. Tanaka I. Tanihata T. Uesaka T. Yamamoto 《Few-Body Systems》2013,54(7-10):1353-1356
Tensor correlations in 4He were studied via the (p, dp) reaction at the incident energy of 392 MeV with a focus on spin configurations of correlated pn pairs in 4He at high relative momenta ${(P_{\rm rel}^{\rm cor})}$ . The preliminary results show that the correlated pn pair at ${P_{\rm rel}^{\rm cor} = 310 {\rm MeV/c}}$ predominantly has the channel spin S = 1, which is consistent with the characteristics of tensor correlations. 相似文献
94.
H. Matsubara M. Takaki T. Uesaka S. Shimoura N. Aoi M. Dozono T. Fujii K. Hatanaka T. Hashimoto T. Kawabata S. Kawase K. Kisamori Y. Kikuch Y. Kubota C. S. Lee H. C. Lee Y. Maeda S. Michimasa K. Miki H. Miya S. Noji S. Ota S. Sakaguchi Y. Sasamoto T. Suzuki L. T. Tang K. Takahisa H. Tokieda A. Tamii K. Yako Y. Yasuda N. Yokota R. Yokoyama J. Zenihiro 《Few-Body Systems》2013,54(7-10):1433-1436
Spectroscopy for neutron-rich nuclei 9He and 12Be has been performed by means of heavy-ion double charge exchange (HIDCX) (18O, 18Ne) reaction on stable target nuclei 9Be and 12C, respectively. Several clear peaks in 12Be at low excitation energy region even above neutron separation energy have been observed in one-shot measurement, whereas no prominent signals of 9He have been observed owing to the small cross section. It is shown that the HIDCX reaction is a new powerful spectroscopic tool for study of unstable neutron-rich nuclei. 相似文献
95.
H. Mardanpour H. R. Amir-Ahmadi R. Benard A. Biegun M. Eslami-Kalantari N. Kalantar-Nayestanaki M. Kiš St. Kistryn A. Kozela H. Kuboki Y. Maeda M. Mahjour-Shafiei J. G. Messchendorp K. Miki S. Noji A. Ramazani-Moghaddam-Arani H. Sakai M. Sasano K. Sekiguchi E. Stephan R. Sworst Y. Takahashi K. Yako 《Few-Body Systems》2008,44(1-4):49-52
A systematic study of three-nucleon force (3NF) effects in break-up reactions has been carried out at KVI at several energies. In this article, the p + d → p + p + n reaction with a polarized-proton beam of 190?MeV will be discussed. The experiment was performed by exploiting a new detector called BINA. Some results for high-precision vector analyzing powers and differential cross sections are presented and compared with state-of-the-art Faddeev calculations with or without 3NF. 相似文献
96.
Kentarou Sakamoto Dr. Misao Akishiba Takahiro Iwata Dr. Kazuya Murata Dr. Seiya Mizuno Dr. Kenichi Kawano Dr. Miki Imanishi Prof. Dr. Fumihiro Sugiyama Prof. Dr. Shiroh Futaki 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(45):20165-20173
Endocytic pathways are practical routes for the intracellular delivery of biomacromolecules. Along with this, effective strategies for endosomal cargo release into the cytosol are desired to achieve successful delivery. Focusing on compositional differences between the cell and endosomal membranes and the pH decrease within endosomes, we designed the lipid-sensitive and pH-responsive endosome-lytic peptide HAad. This peptide contains aminoadipic acid (Aad) residues, which serve as a safety catch for preferential permeabilization of endosomal membranes over cell membranes, and His-to-Ala substitutions enhance the endosomolytic activity. The ability of HAad to destabilize endosomal membranes was supported by model studies using large unilamellar vesicles (LUVs) and by increased intracellular delivery of biomacromolecules (including antibodies) into live cells. Cerebral ventricle injection of Cre recombinase with HAad led to Cre/loxP recombination in a mouse model, thus demonstrating potential applicability of HAad in vivo. 相似文献
97.
Yuki Kobayashi Yu Kojima Ryotaro Miki Toshinobu Seki Takashi Fujihara Yoshihiro Ishimaru Yuya Egawa 《Journal of inclusion phenomena and macrocyclic chemistry》2018,92(3-4):311-317
Herein, we have proposed a single-step preparation of topological gels using vinyl-modified β-cyclodextrin (V-β-CyD) and isoprene. Copolymerization of V-β-CyD and isoprene in an aqueous solution resulted in gelation due to V-β-CyD acting as a novel type of copolymer chain cross-linker. The vinyl moiety of V-β-CyD becomes a part of the copolymer, while the β-CyD moiety of V-β-CyD simultaneously incorporates the isoprene component of the copolymer. V-β-CyD is capable of two different modes of cross-linking at each end, i.e., chemically bonding and mechanically interlocking. Due to the shape of the cross-linking point, we refer to it as figure-of-six cross-linking. Nuclear magnetic resonance analysis showed that the gel contained V-β-CyD and isoprene in an approximately 1:0.3 stoichiometry. The relatively high content of β-CyD was reflected in the character of the gel; the gel swelled in dimethylformamide which is a good solvent of β-CyD. A fluorometric analysis using 6-(p-toluidino)-2-naphthalenesulfonic acid showed that the appended β-CyD was able to accommodate guest molecules. Introduction of an additional vinyl monomer into the gel was also successful. Addition of 4-vinylphenylboronic acid to the preparation procedure yielded a sugar-responsive gel that swelled in the presence of d-fructose. 相似文献
98.
An efficient ruthenium catalyst system for the direct ortho CH borylation of aromatic imines is described. The reaction of tert-butyl-1-arylmethanimines with pinacolborane in the presence of Ru(cod)(cot), followed by hydrolysis, to afford the ortho-formyl-substituted arylboronates. The borylation was achieved with complete mono-selectivity. 相似文献
99.
The total synthesis of myxol stereoisomers 1a,b and deoxymyxol (plectaniaxanthin) stereoisomers 2a,b was accomplished by Wittig reaction of (S)- and (R)-C10-phosphonium salts 8a,b bearing a silyl-protected 1,2-dihydroxy-ψ end group with C30-apocarotenals 6 and 7. The phosphonium salts 8a,b were derived from aldehydes 11a,b possessing a cyclopentylidene ketal moiety, prepared via Sharpless asymmetric epoxidation of allylic alcohol 12 followed by regioselective cleavage of the oxirane ring. We established an analytical HPLC method using a chiral column to separate stereoisomers 1a,b and 2a,b and thus determined the absolute configurations of the natural products. The HPLC analyses established that both myxol and deoxymyxol isolated from bacteria have the 2′S-configuration. 相似文献
100.
We apply our previously developed deconvolution method and interpretation to analyze changes in the OH stretching band [ν(OH) band] of low‐concentration (≤0.2 m) aqueous solutions of NaCl and KCl. We treat these simple, monovalent ions as defects in the hydrogen‐bond network of pure water and quantify the changes in the spectra at low defect concentration with an “order parameter”. Order‐parameter analysis of difference spectra of the two solutions leads to hydration numbers of 7.0±1.0 and 5.9±0.3 for K+ and Na+, respectively. Additionally, we find that changes in the ν(OH) band due to low concentrations of ions result from changes in the topology of the hydrogen‐bond network. 相似文献