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Song HC Li WM Liu GR Xu ZL 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2003,59(9):2041-2048
The maximum absorption wavelengths (lambda(a-max)), absorption coefficient (epsilon), maximum emission wavelengths (lambda(e-max)), fluorescent quantum yields (phi(f)), and second-order nonlinear polarizations (beta(xxx)) of seventeen 4,4'-bis-(2-(substituted-styryl))biphenyl and three 1,4-bis-(2-(substituted-styryl))benzene were measured. The results showed that some of this series of compounds possess high fluorescent quantum yields in DMF, such as, 2 (0.801), 3 (0.680), 5 (0.565), 15 (0.538) 16 (0.848), 18 (2.175), 19 (1.314) and 20 (1.060), as compared with quinine-sulfuric acid. They could be used as fluorescent whiteners and fluorescent colorants. Some of these compounds were of a high beta(xxx) values, such as in DMSO, 2 (29.00/10(-30) m(5)c(-1)), 3 (25.29/10(-30) m(5)c(-1)), 8 (21.79/10(-30) m(5)c(-1)) and 9 (24.08/10(-30) m(5)c(-1)). Electron-withdrawing substituent NO(2), which is attached to the two terminal phenyl rings could cause lambda(a-max) obviously to be shorter, but it made lambda(e-max) change longer. Electron-donating substituent at two end benzene rings, such as OCH(3), N((CH(3))(2)), even Cl, could make lambda(a-max) and lambda(e-max) longer, and the larger the electron-donating ability of the substituent, the longer the lambda(a-max) and lambda(e-max). This influence of 4-position substituent on lambda(a-max) or lambda(e-max) is obviously larger than that of 2-position substituent, and the action of substituent on 2-position is larger than that of substituent on 3-position. The values of lambda(a-max) and lambda(e-max) of biphenyl compounds 2 or 3 were respectively close to these values of corresponding benzene compounds 18 or 19. 相似文献
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TAN Song-De WEI Ying WANG Bo XU Zun-Le CHEN Wen-Hua 《有机化学》2003,23(Z1):400-401
The biological importance of acetylcholine spurs the efforts to construct its synthetic receptors with the aims to develop acetylcholine sensor devices. Among the various building blocks used to synthesize artificial acetylcholine receptors, resorcin [4 ]arenes, [1] which can be conveniently obtained from the acid-catalyzed condensation of resorcinol with aldehyde, were shown to serve as one of the most strongest synthetic receptors for choline type guests. 相似文献
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Tan SD Chen WH Satake A Wang B Xu ZL Kobuke Y 《Organic & biomolecular chemistry》2004,2(19):2719-2721
This communication describes the facile synthesis of tetracyanoresorcin[4]arene and its high and pH dependent affinities toward biologically important acetylcholine in the physiological pH region. 相似文献
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The inclusion complexes of tetracyanoresorcin[4]arene with six quaternary ammonium cations—biologically important acetylcholine and choline, tetramethyl ammonium, tetraethyl ammonium, tetrapropyl ammonium and tetrabutyl ammonium—were studied by means of electrospray ionization mass, fluorescence and NMR spectrometries. The results indicate that tetracyanoresorcin[4]arene shows high affinity toward these ammoniums and is capable of recognizing their sizes. Spectrometric evidences for the size discrimination of quaternary ammonium cations by tetracyanoresorcin[4]arene are preseneted. 相似文献
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Copper amine complexes were used to mimic oxidases in the biomimetic oxidation of organic compounds[1]. Masahiro Noji and coworkers[2] reported the oxidative coupling of 2-naphthol into high yield of 1,1'-bi-2-naphthol (1) by using catalytical amount of CuCl-tetramethylethylenediamine complex at the presence of O2. Here we report the catalytic oxidation of 1 with copper amine complexes. 相似文献
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用乙酸钠作催化剂, 可使Azlatones 和低级醇顺利地进行酯交换反应. 文中分别使用带不同取代基的Azlatones在乙酸钠催化下与甲醇, 乙醇或乙二醇共热0.5~2.5小时, 以73~94%的分离产率制得21个酯交换产物. 相似文献
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