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71.
Methylene sp3 carbon–hydrogen bond activation of N-picolinoylcycloalkylamines provides a useful method for synthesizing cis-3-arylated cycloalkylamine derivatives. Pd(II) species catalyzed the γ-arylation of N-picolinoylcycloalkylamines with aryl iodides in the presence of silver carbonate to afford cis-3-arylated N-picolinoylalkylamines in up to 87% yield. Hydrolysis of the amide linkage to give the corresponding cis-3-arylated cycloalkylamines was also demonstrated. 相似文献
72.
73.
Xiaolei Wang Miho Emoto Atsushi Sugimoto Yusuke Miyake Kaori Itto Mitsuo Amasaka Shu Xu Hiroshi Hirata Hirotada Fujii Hirokazu Arimoto 《Tetrahedron letters》2014
A scalable synthetic route for 15N-labeled 4-oxo-2,2,6,6-tetraethylpiperidine nitroxide (15N-TEEPONE) is described. This 15N-labeled nitroxide is suitable for electron paramagnetic resonance imaging of brain, and its higher sensitivity compared with that of its 14N-counterpart is an important advantage of the labeled derivative. 相似文献
74.
Chaolumen Hiroki Enno Dr. Michihisa Murata Prof. Dr. Atsushi Wakamiya Prof. Dr. Yasujiro Murata 《化学:亚洲杂志》2014,9(11):3136-3140
Perylene bisimides (PBIs) are fascinating dyes with various potential applications. To study the effects of introducing a dibenzo‐fused structure to the perylene moiety, π‐extended PBI derivatives with a dibenzo‐fused structure at both of the a and f bonds were synthesized. The twisted structure was characterized by X‐ray crystal structure analysis. In the cyclic voltammograms, the dibenzo[a,f]‐fused PBI showed a reversible oxidation wave at much less positive potential, relative to a dibenzo[a,o]‐fused PBI derivative. These data indicated that two ring fusions at both sides of a naphthalene moiety, which construct a tetracene core, effectively raise the HOMO level compared to fusion of one ring at each naphthalene moiety (two anthracene cores). The dibenzo[a,f]‐fused PBI derivative showed an absorption band at 735 nm with a shoulder band reaching 900 nm. 相似文献
75.
Kenneth P. Mineart Xi Jiang Hiroshi Jinnai Atsushi Takahara Richard J. Spontak 《Macromolecular rapid communications》2015,36(5):432-438
Recent developments regarding charged multiblock copolymers that can form physical networks and exhibit robust mechanical properties herald new and exciting opportunities for contemporary technologies requiring amphiphilic attributes. Due to the presence of strong interactions, however, control over the phase behavior of such materials remains challenging, especially since their morphologies can be solvent‐templated. In this study, transmission electron microscopy and microtomography are employed to examine the morphological characteristics of midblock‐sulfonated pentablock ionomers prepared from solvents differing in polarity. Resultant images confirm that discrete, spherical ion‐rich microdomains form in films cast from a relatively nonpolar solvent, whereas an apparently mixed morphology with a continuous ion‐rich pathway is generated when the casting solvent is more highly polar. Detailed 3D analysis of the morphological characteristics confirms the coexistence of hexagonally‐packed nonpolar cylinders and lamellae, which facilitates the diffusion of ions and/or other polar species through the nanostructured medium.
76.
Yohei Saito Atsushi Mizokami Kouji Izumi Renato Naito Masuo Goto Kyoko Nakagawa-Goto 《Molecules (Basel, Switzerland)》2021,26(9)
α-Trifluoromethyl chalcones were prepared and evaluated for their antiproliferative activities against androgen-independent prostate cancer cell lines as well as five additional types of human tumor cell lines. The most potent chalcone 5 showed superior antitumor activity in vivo with both oral and intraperitoneal administration at 3 mg/kg. Cell-based mechanism of action studies demonstrated that 5 induced cell accumulation at sub-G1 and G2/M phases without interfering with microtubule polymerization. Furthermore, several cancer cell growth-related proteins were identified by using chalcone 5 as a bait for the affinity purification of binding proteins. 相似文献
77.
Hiromi NAKANISHI Atsushi MORI Kouki TAKEDA Houdo TANAKA Natsuko KOBAYASHI Keitaro TANOI Takashi YAMAKAWA Satoshi MORI 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2015,91(4):160-174
Six months after the explosion of TEPCO’s Fukushima Dai-ichi nuclear power plant, radioactive
silver (110mAg), was detected in concentrations of 3754 Bq/kg in Nephila
clavata (the orb-web spider; Joro-gumo in Japanese) collected at
Nimaibashi, Iitate village in Fukushima Prefecture, whereas 110mAg in the soil was
43.1 Bq/kg. A survey of 35 faunal species in the terrestrial environment during the 3.5 years
after the accident showed that most of Anthropoda had two orders higher 110mAg in
their tissues than soils, although silver is not an essential element for their life. However,
tracing of the activity of 110mAg detected in spider Atypus karschi
collected regularly at a fixed location showed that it declined much faster than the physical
half-life. These results suggest that 110mAg was at once biologically concentrated
by faunal species, especially Arthropoda, through food chain. The factors affecting the
subsequent rapid decline of 110mAg concentration in faunal species are
discussed. 相似文献
78.
Prof. Yutaka Maeda Yuhei Hasuike Prof. Kei Ohkubo Atsushi Tashiro Shinya Kaneko Masayuki Kikuta Dr. Michio Yamada Prof. Tadashi Hasegawa Prof. Takeshi Akasaka Dr. Jing Zhou Prof. Jing Lu Prof. Shigeru Nagase Prof. Shunichi Fukuzumi 《Chemphyschem》2014,15(9):1821-1826
This report describes the photochemical behavior of single‐walled carbon nanotubes (SWNTs) in the presence of propylamine. The SWNTs are characterized by absorption and Raman spectroscopy. The spectral changes due to photoirradiation indicate that reactions occur predominantly with the metallic SWNTs and small‐diameter SWNTs. The detection of amine radicalcation species by ESR spectroscopy reveals photoinduced electron transfer from the amine to the excited SWNTs. After exposure of the photoirradiated SWNTs to air, the characteristic spectra were recovered, except for that of the small‐diameter SWNTs. The results suggest that, after photoreduction of the SWNTs, subsequent selective sidewall functionalization of the small‐diameter SWNTs occurs. 相似文献
79.
Hong Tho Le Dr. Chen-Gang Wang Prof. Dr. Atsushi Goto 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(24):9446-9450
Liquid vinyl monomers were converted into solid crystals via halogen bonding. They underwent solid-phase radical polymerizations through heating at 40 °C or ultraviolet photo-irradiation (365 nm). The X-ray crystallography analysis showed the high degree of monomer alignment in the crystals. The polymerizations of the solid monomer crystals yielded polymers with high molecular weights and relatively low dispersities because of the high degree of the monomer alignment in the crystal. As a unique application of this system, the crystalized monomers were assembled to pre-determined structures, followed by solid-phase polymerization, to obtain a two-layer polymer sheet and a three-dimensional house-shaped polymer material. The two-layer sheet contained a unique asymmetric pore structure and exhibited a solvent-responsive shape memory property and may find applications to asymmetric membranes and polymer actuators. 相似文献
80.
Ribeiro Geyse Adriana Corrêa da Rocha Cláudia Quintino Veloso William Barros Dantas Luiza Maria Ferreira Richter Eduardo Mathias da Silva Iranaldo Santos Tanaka Auro Atsushi 《Journal of Solid State Electrochemistry》2020,24(8):1759-1768
Journal of Solid State Electrochemistry - Rapid methods using batch injection analysis (BIA) with amperometric detection were developed for the determination of quercetin extracted from the... 相似文献