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901.
Kazuyuki Onodera Gen-ichi Furusawa Masanobu Kojima Masahiro Tsuchiya Shin Aihara Ryoichi Akaba Hirochika Sakuragi Katsumi Tokumaru 《Tetrahedron》1985,41(11):2215-2220
Reactions of various organic compounds induced by excitation of their contact charge transfer (CCT) pairs with oxygen were classified into three types of behaviour on the basis of reaction products. It is proposed that the excited state of the CCT pairs gives the products through the most isoenergetic course along the plausible exothermic pathway. 相似文献
902.
903.
Shimada Y Akane H Taniguchi N Matsuhisa A Kawano N Kikuchi K Yatsu T Tahara A Tomura Y Kusayama T Wada K Tsukada J Tsunoda T Tanaka A 《Chemical & pharmaceutical bulletin》2005,53(7):764-769
To find a new series of arginine vasopressin (AVP) V1A receptor antagonists, the influence of the 2-phenyl group of 2-phenyl-4'-[(2,3,4,5-tetrahydro-1H-1-benzazepin-1-yl)carbonyl]benzanilide (7) was investigated. Replacement of the 2-phenyl group by a 2-ethyl-1H-imidazol-1-yl group was effective in yielding a V1A-selective compound. Moreover, this imidazolyl group was introduced in the same position in YM-35471 (6), and further studies of these compounds were performed. Consequently, we found that the (Z)-4'-({4,4-difluoro-5-[(N-cyclopropylcarbamoyl)methylene]-2,3,4,5-tetrahydro-1H-1-benzazepin-1-yl}carbonyl)-2-(2-ethyl-1H-1-imidazol-1-yl)benzanilide (9f) exhibited highly potent affinity and selectivity, and was the most potent antagonist for the V1A receptor among our compounds. The synthesis and pharmacological evaluation of these compounds are described in this paper. 相似文献
904.
The solid solution Fe(Nb1?xWx)O4 (0 ≦ x ≦ 1) with wolframite-type structure has been prepared under argon atmosphere at 1000°C. The change of unit cell parameters is not linear, owing to the zigzag chain of octahedra along the c-axis. The results of magnetic susceptibility and Mössbauer effect measurements indicate the existence of a mixed valence state of iron ions. 相似文献
905.
Chul-Joong Yoon Hiroshi Ikeda Ryoichi Kojin Tsukasa Ikeda Fujio Toda 《Journal of inclusion phenomena and macrocyclic chemistry》1987,5(1):85-91
-cyclodextrin-1,4-dihydronicotinamide can reduce cytochrome c in aqueous solution, by adding redox dyes as mediators. In the reduction of cytochrome c mediated by redox dyes, the speeds of reduction differ depending on the activities of the dyes. Inhibition using cyclohexanol occured in the presence of nile blue or methylene blue, and showed competitive inhibition. In the case of using neutral red as a mediator, the reduction was accelerated by adding cyclohexanol. Reaction rate constants of this reaction were independent of the redox potential of the redox dyes. 相似文献
906.
Kapoor MP Inagaki S Ikeda S Kakiuchi K Suda M Shimada T 《Journal of the American Chemical Society》2005,127(22):8174-8178
The bridged allylorganosilanes 1,4-bis(diallylethoxysilyl)benzene and 1,4-bis(triallylsilyl)benzene are presented as new precursors for the surfactant-assisted synthesis of ordered mesoporous organosilica with pore walls having crystal-like molecular-scale periodicity. This approach provides a new route to the formation of periodic mesostructures with crystal-like pore walls. The synthesis method presented is applicable to the preparation of mesoporous organosilica with bulky organic groups, the precursors of which are typically impossible to obtain in high purity. 相似文献
907.
Sh. Sasaki E. Tega A. Shimada S. Akahori T. Suzuki K. Okuno K. Kondo 《Journal of Radioanalytical and Nuclear Chemistry》2003,255(1):91-95
The separation efficiency of hollow-filament polyimide membranes for 3H and 41Ar is preliminarily examined for a potential application to continuous gas monitoring systems for analysis of stack emission from accelerator facilities. The basic gas separation characteristics of the membranes are experimentally investigated, and a preliminary gas monitor design is proposed. The results indicate that the membranes are capable of selectively enriching hydrogen by more than 25 times, with negligible variation with respect to the species of isotope. 相似文献
908.
[reaction: see text] The palladium complex prepared from DPPF and Cp(eta3-C3H5)Pd is an effective catalyst for the alkylation of active methine compounds with benzylic carbonates under neutral conditions. The addition of 1,5-cyclooctadiene brought about remarkable improvement in the lifetime of the palladium catalyst, which led to high yields of the desired benzylation products. 相似文献
909.
Enhanced infrared ATR spectra were measured for Langmuir films of CuPc deposited on PE and PVdC overlaid on PET, by using thin metal (Ni or Ag) films. The apparent intensity ratios for the bands ascribed to the upper layer were much larger than for those of the lower layer. The ratio depended on the nature as well as the mass thickness of the metal films. The mechanism of the enhancement was discussed in terms of SPP and multiple reflection effects. 相似文献
910.
Six reagents possessing ferrocene as an electrophore were prepared and evaluated for pre-column derivatization of amino compounds for their determination by high-performance liquid chromatography with electrochemical detection. The utility of these reagents was investigated employing phenethylamine as a model compound. Among these six, N-succinimidyl 3-ferrocenylpropionate was the best with respect to reactivity, stability and electrochemical properties. The developed method was applied to the determination of putrescine formed from ornithine by ornithine decarboxylase. 相似文献