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排序方式: 共有245条查询结果,搜索用时 0 毫秒
1.
Takumi Watanabe Yuichiro Nishizawa Haruka Minato Dr. Chihong Song Prof. Dr. Kazuyoshi Murata Prof. Dr. Daisuke Suzuki 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(23):8934-8938
The three-dimensional structure of nanocomposite microgels was precisely determined by cryo-electron micrography. Several nanocomposite microgels that differ with respect to their nanocomposite structure, which were obtained from seeded emulsion polymerization in the presence of microgels, were used as model nanocomposite materials for cryo-electron micrography. The obtained three-dimensional segmentation images of these nanocomposite microgels provide important insights into the interactions between the hydrophobic monomers and the microgels, that is, hydrophobic styrene monomers recognize molecular-scale differences in polarity within the microgels during the emulsion polymerization. This result led to the formation of unprecedented multi-layered nanocomposite microgels, which promise substantial potential in colloidal applications. 相似文献
2.
Novel synthetic procedure of heterocycles was developed using nickel-mediated alkylative carboxylation, and the total synthesis of erythrocarine was achieved using this method and RCM of dienyne as the key steps. [reaction: see text] 相似文献
3.
The synthesis and thermal decomposition of a series of 3-azido-4-benzylideneamino-s-triazoles are described. The decompositions resulted in a loss of nitrogen and intra-molecular cyclization at the carbon atom of the azomethine linkage to produce 1H-2-aryl-s-triazolo-[3,2-c]-s-triazoles. 相似文献
4.
5.
K Take K Okumura K Takimoto M Ohtsuka Y Shiokawa 《Chemical & pharmaceutical bulletin》1992,40(4):899-906
A series of 1,1'-biphenyl-2,6-dicarboxylic acid diesters with an aminoalkyl group in the ester function were synthesized and examined for their inhibitory activity on detrusor contraction in vitro and in vivo. In the in vivo test, arrhythmia was observed as a side effect. Among those compounds synthesized, 2-methyl 6-[4-(1-methylpiperidinyl)] 3-hydroxy-5-methyl-2'-nitro-1,1'-biphenyl-2,6-dicarboxylate (18) showed strong inhibitory activity on detrusor contractions in vivo (ED50 = 0.54 mg/kg i.v., ED50 = 7.2mg/kg i.d.) and good separation from the side effect. Compound 18 was chosen for further pharmacological evaluation as an agent for the treatment of overactive detrusor. 相似文献
6.
Mori M Saito N Tanaka D Takimoto M Sato Y 《Journal of the American Chemical Society》2003,125(19):5606-5607
Novel alkenylative cyclization of enyne was developed using Cp*RuCl(cod) under ethylene gas at room temperature. 相似文献
7.
5,11-Diazadibenzo[hi,qr]tetracene: Synthesis,Properties, and Reactivity toward Nucleophilic Reagents
Dr. Keisuke Fujimoto Satoshi Takimoto Shota Masuda Dr. Toshiyasu Inuzuka Kazutaka Sanada Prof. Dr. Masami Sakamoto Prof. Dr. Masaki Takahashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(35):8951-8955
5,11-Diazadibenzo[hi,qr]tetracene was synthesized as a new nitrogen-substituted polycyclic heteroaromatic compound by Pd-catalyzed cycloisomerization of an alkyne precursor followed by oxidative cyclization with bis(trifluoroacetoxy)iodobenzene. The substitution of imine-type nitrogen atoms significantly enhanced its electron-accepting character and facilitated the direct nucleophilic addition of arylamines under strongly basic conditions to afford the desired amino-substituted products. The introduction of amino groups induced a remarkable red-shift in their absorption spectra; the tetrasubstituted product exhibited intense near-infrared absorbing property. Furthermore, the π-electronic system, which includes a redox-active 1,4-diazabutadiene moiety, underwent reversible interconversion to its corresponding reduced form upon reduction with NaBH4 and aerobic oxidation. 相似文献
8.
Dr. Tsubasa Nakashima Haruka Fujimori Dr. Kohsuke Ohmatsu Prof. Takashi Ooi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(36):9253-9256
Intermediary radical cations, generated through single-electron oxidation of enol silyl ethers by excited Ir-based photocatalysts, can be exploited as Brønsted acids for the activation of heteroarylcyanides. This strategy enables the direct allylic C−H heteroarylation of enol silyl ethers under visible-light irradiation. 相似文献
9.
Yasunobu Kotani Haruka Yasuda Dr. Kenji Higashiguchi Prof. Kenji Matsuda 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(43):11158-11166
An amphiphilic rectangular-shaped photochromic diarylethene bearing two hydrophobic alkyl chains and two hydrophilic tri(ethylene glycol) chains was synthesized, and its photoinduced morphological transformation in water was investigated. Two unexpected phenomena were revealed in the course of the experiments: a re-entrant photoinduced macroscopic morphological transformation and temperature-dependent kinetic products of supramolecular assembly. When the pure closed-ring isomer was dispersed in water, a re-entrant photoinduced morphological transformation, that is, a photoinduced transition from the hydrated phase to the dehydrated phase and then back to the hydrated phase, was observed by optical microscopy upon irradiation with green light at 20 °C; this was interpreted by the V-shaped phase diagram of the LCST transition. The aqueous assembly of the pure closed-ring isomer was controlled by changing the temperature; specifically, rapid cooling to 15 and 5 °C gave J and H aggregates, respectively, as the kinetic products. The thermodynamic product at both temperatures was a mixture of mostly H aggregate with a small amount of J aggregate. This behavior was rationalized by the temperature-dependent potential energy surface of the supramolecular assembly. 相似文献
10.
Dr. Tatsuya Takimoto Prof. Hideaki Sasaki Prof. Hirohito Tsue Dr. Hiroki Takahashi Prof. Alexander D. MacKerell Jr. Ayumi Nakamura Katsuya Nakano Eori Okazaki Tatsuki Betsuyaku Ryosuke Tachibana Dr. Kazuhito Hioki Dr. Ozge Yoluk Dr. Sunhwan Jo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(5):1648-1654
A simple approach to the synthesis of heterocyclophane consisting of two 4,4’-bithiazoles has been developed in mild conditions. The heterocyclophane with two short chains was conveniently prepared by Hantzsch thiazoles synthesis using the reaction of 3-tert-butoxycarbonyl-3-azapentanethiocarboxamide with 1,4-dibromobutane-2,3-dione in methanol under reflux for only 15 min. Amino groups at the linkers of this heterocyclophane can be functionalized to give acylated and carbamate derivatives. Their properties as protein kinase inhibitors were investigated, and one of the heterocyclophanes exhibited specific anti-activity for c-mesenchymal epithelial transition factor (IC50=603 nm ), among seven types of protein kinases investigated. The computational site identification by ligand competitive saturation method was used to determine why the one heterocyclophane exhibited strong anti-activity for c-mesenchymal epithelial transition factor. 相似文献