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1.
The chemiluminescence (CL) intensities of various indole derivatives substituted with a glyoxylyl group at the 3-position and a hydroxyl group at the 5-position of the indole ring were compared upon the addition of H2O2 in alkaline media. The CL intensities of 3-indoleglyoxylyl chloride, 3-indoleglyoxylic acid, 5-hydroxyindole and 5-benzyloxyindole in CH3CN were 5.9-, 48-, 5.9- and 3.3-fold stronger than that of 3-methylindole. A lasting CL of 3-indoleglyoxylyl chloride was found. Under appropriate conditions, the CL emission reached a maximum within 10 min after the addition of H2O2 in the presence of NaOH, and the intensity was retained for 25 min. One of the final products via the CL reaction of 3-indoleglyoxylyl chloride was indole-3-carboxylic acid. 3-Indoleglyoxylyl chloride emitted light by decompositions via both dioxetane and dioxetanedione. An enhancement effect of beta-cyclodextrin and bovine serum albumin on the CL of 3-indoleglyoxylyl chloride was also found. 相似文献
2.
Takanari Yasui Takeshi Ohtsuka Tetsu Suzuki Shigeki Okajima Kazuya Nakayama Mitsuru Tomioka Katsuhiro Kamimura Takeo Namekata Hiroaki Minamide Hiromasa Ito 《International Journal of Infrared and Millimeter Waves》2006,27(2):199-210
A new, wide-band, high-speed and high-sensitivity THz detector has been developed. The prototype detector consists of a parabolic
cylindrical mirror, a long wire antenna and a Schottky barrier diode. Direct detection measurements have shown a stable sensitivity
of 150 ± 50 V/W for 1–2 THz without any adjustments. The long wire antenna was fixed at the focus of parabolic cylindrical
mirror then it has been realized less operation steps, easy coupling to the external THz signals and a dramatic enhancement
in the practicality of this system. The optically polished mirror and frosted surface one showed comparable sensitivities,
thus easy polishing and less cost mirror fabrication can be applied for this system. The radiation pattern showed a maximum
radiation angle of approximately 23° with its dominant main lobe, which was attributed to the wire antenna character and confirmed
good agreements with classical antenna theory. 相似文献
3.
4.
H. Kawaguchi S. Kataiwa T. Mita Y. Ohtsuka T. Takeuchi S. Kobayashi 《Colloid and polymer science》1990,268(12):1167-1173
Dichlorophene was used as a model drug. Drug-carrying latex particles were prepared by soap-free emulsion copolymerization of dichlorophene acrylate with some hydrophilic methacrylate comonomers. The comonomers used affected not only the structure and colloidal stability of particles, but also the drug-activity of particles. Preliminary study of the drug activity revealed that highly hydrophilic latex particles were very stable and too inactive to be engulfed by amoebae and kill them. On the contrary, less hydrophilic particles carrying a large amount of drug can be an effective device to release drugs at a moderate rate to fight against extracelluar targets such as parasites. 相似文献
5.
6.
Mass spectra of ginsenoside-Rg1 deca-acetate 1 Siehe Lit.2. and the related dammaran-type triterpene saponin acetates have been studied and a comment is given on the structure of panaxoside A (=ginsenoside-Rg1) proposed by Elyakov, et al . 相似文献
7.
Suzuki Y Yamauchi K Muramatsu K Sato M 《Chemical communications (Cambridge, England)》2004,(23):2770-2771
Chiral N-heterocyclic carbenes, which are derived from C2-symmetric 1,3-bis(1-arylethyl)imidazolium salts, catalyze enantioselective acylation of racemic secondary alcohols. 相似文献
8.
Hideaki Hioki Yumiko Ohnishi Miwa Kubo Emi Nashimoto Yukinori Kinoshita Miho Samejima Mitsuaki Kodama 《Tetrahedron letters》2004,45(3):561-564
A fluorescence-labeled calix[4]arene library substituted with peptides at the upper rim was synthesized. Screening of the library for binding a dye-labeled oligopeptide indicated that some peptidocalix[4]arenes selectively bind the oligopeptide. The chemosensitivity of the library members for a target peptide was also investigated. 相似文献
9.
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
10.
Uchiyama M Miyoshi T Kajihara Y Sakamoto T Otani Y Ohwada T Kondo Y 《Journal of the American Chemical Society》2002,124(29):8514-8515
We have developed new methods for preparing functionalized benzynes through deprotonative zincation as a key reaction using R2Zn(TMP)Li, and we also describes dramatic ligand effects on the benzyne formation. Deprotonative zincation of various meta-substituted bromobenzenes with Me2Zn(TMP)Li proved effective for the one-pot generation of various 3-functionalized benzynes, particularly those electrophilic substituents such as ester, amide, and cyano. On the other hand, zincation with tBu2Zn(TMP)Li, followed by electrophilic trapping (with I2) proved a powerful tool for the preparation of 1,2,3-trisubstituted aromatic compounds.8 The resultant 1,2,3-trisubstituted benzenes are available as precursors for generation of 3-substituted benzynes by halogen-zinc exchange reactions with Me3ZnLi. These methods offer far greater generality than previous methods for the synthesis of functionalized asymmetric benzynes, and should be of value in new syntheses of various natural products and functional materials. In addition, these results underline the utility of spectator ligands on the central metal of ate complexes as a tunable functionality in the development of new ate complex-promoted reactions. 相似文献