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91.
Hayashi Y Obata N Tamaru M Yamaguchi S Matsuo Y Saeki A Seki S Kureishi Y Saito S Yamaguchi S Shinokubo H 《Organic letters》2012,14(3):866-869
A biphenyl-fused BODIPY was synthesized through a facile oxidative cyclization of peripheral aryl-substituents at the β-position of the BODIPY unit. The extended π-system of the fused BODIPY induces near-infrared (NIR) absorption and strong π-π interactions in the solid state. These features are beneficial for the application of the dye as a functional material. The biphenyl-fused BODIPY dye was demonstrated to exhibit photocurrent conversion ability on the basis of its n-type semiconducting property. 相似文献
92.
An α-cyclodextrin-based size-complementary [3]rotaxane with an alkylene axle was selectively synthesized in one pot via an end-capping reaction with 2-bromophenyl isocyanate in water. Thermal degradation of the [3]rotaxane product yielded not only the original components but also the [2]rotaxane. Thermodynamic studies suggested a stepwise deslippage process. 相似文献
93.
Dr. Yosuke Demizu Prof. Mitsunobu Doi Dr. Masaaki Kurihara Prof. Tokumi Maruyama Prof. Hiroshi Suemune Prof. Masakazu Tanaka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(8):2430-2439
Chiral cyclic α,α‐disubstituted amino acids, (3S,4S)‐ and (3R,4R)‐1‐amino‐3,4‐(dialkoxy)cyclopentanecarboxylic acids ((S,S)‐ and (R,R)‐Ac5cdOR; R: methyl, methoxymethyl), were synthesized from dimethyl L ‐(+)‐ or D ‐(?)‐tartrate, and their homochiral homoligomers were prepared by solution‐phase methods. The preferred secondary structure of the (S,S)‐Ac5cdOMe hexapeptide was a left‐handed (M) 310 helix, whereas those of the (S,S)‐Ac5cdOMe octa‐ and decapeptides were left‐handed (M) α helices, both in solution and in the crystal state. The octa‐ and decapeptides can be well dissolved in pure water and are more α helical in water than in 2,2,2‐trifluoroethanol solution. The left‐handed (M) helices of the (S,S)‐Ac5cdOMe homochiral homopeptides were exclusively controlled by the side‐chain chiral centers, because the cyclic amino acid (S,S)‐Ac5cdOMe does not have an α‐carbon chiral center but has side‐chain γ‐carbon chiral centers. 相似文献
94.
Haiying Fu Mingzhang Lin Yusa Muroya Yosuke Katsumura 《Research on Chemical Intermediates》2012,38(1):135-145
The oxidation processes of the radiation-generated, three-electron-bonded intermediates AcMet2 [S??S]+ and AcMet [S??Br] were investigated by pulse radiolysis via their reactions with tryptophan (TrpH). These intermediates were derived from N-acetyl-methionine amide (N-AcMetNH2) and N-acetyl-methionine methyl ester (N-AcMetOMe). The bimolecular rate constant k of the reaction between each intermediate and l-tryptophan (TrpH) was measured. For N-AcMetNH2, k for the reaction of AcMet2 [S??S]+ with TrpH were 3.4?×?108 and 2.2?×?108?dm3?mol?1?s?1 at pH?=?1 and 4.5, respectively. For N-AcMetOMe, k for the reaction of AcMet2 [S??S]+ with TrpH were 4.0?×?108 and 2.8?×?108?dm3?mol?1?s?1 at pH 1 and 4.5, respectively. The rate constants for the intermolecular transformation of Met [S??Br] into TrpH+ or Trp were also estimated. For N-AcMetNH2, k for the reaction of AcMet2 [S??Br] with TrpH were 2.6?×?108 and 3.3?×?108?dm3?mol?1?s?1 at pH 1 and 4.5, respectively. Related mechanisms were discussed. 相似文献
95.
Yosuke Kataoka 《Journal of Molecular Liquids》2001,90(1-3):35-43
Molecular dynamics simulations on Lennard-Jones mixture in the supercritical region are performed. The number of the molecules in the unit cell is 23328 and the mole fraction is 0.5. The concentration fluctuations near the critical point are large compared to the ideal mixing. The mutual diffusion coefficient normalized by the self-diffusion coefficient has a small value near the critical density because of the large concentration fluctuation. The heat capacity, partial molar volume and correlation lengths of density and concentration in the supercritical region are compared with those at the normal density. 相似文献
96.
Shin-ichi Matsuoka Naoto Ogiwara Yosuke Uehara Takashi Ishizone 《Macromolecular Symposia》2006,240(1):206-212
Ring-opening polymerizations of [3.3.1]propellane derivatives, 1,3-dehydroadamantane ( 1 ) and 5-butyl-1,3-dehydroadamantane ( 2 ), were carried out with CF3SO3H in CH2Cl2 at 0 °C for 6–42 h. The central σ-bonds in 1 and 2 were exclusively opened to afford novel poly([3.3.1]propellane)s, poly(1,3-adamantane)s, in 52–95% yields. The resulting poly( 2 ) possessing flexible butyl substituent was soluble in chloroform, THF, and 1,2-dichlorobenzene, and the degree of polymerization was estimated to be greater than 30, while the poly( 1 ) was hardly soluble in the common organic solvents. All aliphatic poly( 1 ) and poly( 2 ) showed high thermal stability, their 10% weight loss temperatures were 421 and 486 °C, respectively. 相似文献
97.
Optical Review - We demonstrate distributed measurement of the polarization beat length along single-mode optical fibers (SMFs) using slope-assisted Brillouin optical correlation-domain... 相似文献
98.
Dr. Yosuke Hisamatsu Koki Otani Hiroshi Takase Dr. Naoki Umezawa Prof. Dr. Tsunehiko Higuchi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(21):6489-6499
There is increasing interest in the development and applications of synthetic receptors that recognize target biomolecules in aqueous media. We have developed a new tweezer-type synthetic receptor that gives a significant fluorescence response upon complexation with heme in aqueous solution at pH 7.4. The synthetic receptor consists of a tweezer-type heme recognition site and sulfo-Cy5 as a hydrophilic fluorophore. The receptor–heme complex exhibits a supramolecular amphiphilic character that facilitates the formation of self-assembled aggregates, and both the tweezer moiety and the sulfo-Cy5 moiety are important for this property. The synthetic receptor also exhibits significant fluorescence responses to biliverdin and bilirubin, but shows very weak fluorescence responses to flavin mononucleotide, folic acid, and nicotinamide adenine dinucleotide, which contain smaller π-scaffolds. 相似文献
99.
Yosuke Watanabe 《Tetrahedron letters》2004,45(30):5795-5797
A new efficient method of MOM etherification of secondary alcohols using 2-(chloromethyl)-3,5-dioxahex-1-ene (Okahara's reagent) is reported. 相似文献