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201.
Jun Yue Bai Liang Wang Hong Jing Wang Peng Fei Huang Yu Qing Zhao Sheng Di Fan 《Mikrochimica acta》2006,156(3-4):321-326
The electrochemical behavior of epinephrine (EP) at a mercaptoacetic acid (MAA) self-assembled monolayer modified gold electrode
was studied. The MAA/Au electrode is demonstrated to promote the electrochemical response of epinephrine by cyclic voltammetry.
The possible reaction mechanism is also discussed. The diffusion coefficient D of EP is 6.85 × 10−6 cm2 s−1. In 0.1 mol L−1 phosphate buffer (pH 7.20), a sensitive oxidation peak was observed at 0.177 V, and the peak current is proportional to the
concentration of EP in the range of 1.0 × 10−5–2.0 × 10−4 mol L−1 and 1.0 × 10−7–1.0 × 10−6 mol L−1. The detection limit is 5 × 10−8 mol L−1. The modified electrode is highly stable and can be applied to the determination of EP in practical injection samples. The
method is simple, quick, sensitive and accurate. 相似文献
202.
Nobukatsu Nemoto Keiichiro Kakimoto Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2002,40(11):1698-1705
This work deals with the cationic ring‐opening polymerization of cyclic thiocarbonates with a norbornene or norbornane moiety, that is, 5,5‐(bicyclo[2.2.1]hept‐2‐ene‐5,5‐ylidene)‐1,3‐dioxane‐2‐thione ( TC1 ) or 5,5‐(bicyclo[2.2.1]heptane‐5,5‐ylidene)‐1,3‐dioxane‐2‐thione ( TC2 ), respectively. The reaction of TC1 initiated by trifluoromethanesulfonic acid (TfOH), methyl trifluoromethanesulfonate (TfOMe), boron trifluoride etherate (BF3OEt2), or triethyloxonium tetrafluoroborate (Et3OBF4) afforded unidentified products; however, TC1 underwent cationic ring‐opening polymerization with methyl iodide as an initiator to afford polythiocarbonate because the propagating end was stabilized by the covalent‐bonding property. The polymerization of TC2 initiated by TfOH, TfOMe, BF3OEt2, or Et3OBF4 afforded polythiocarbonate with good solubility in common organic solvents and a narrow molecular weight distribution because of the absence of a double‐bond moiety. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1698–1705, 2002 相似文献
203.
4-Morpholinoacetophenone thiosemicarbazone, MAPT, and its nickel(Ⅱ) and copper(Ⅱ) complexes have been prepared and characterized by elemental analysis, magnetic susceptibility, spectral methods (FT-IR, ^1H NMR) and cyclic voltammetry. Electrochemical behaviors of the complexes have been studied by cyclic voltammetry in DMF media showing metal centered reduction processes for both of them. The redox properties, nature of the electrode processes and the stability of the complexes were discussed. [Cu(MAPT)2]Cl2 complex shows Cu(Ⅱ)/Cu(Ⅰ) couple and quasi-reversible wave associated with the Cu(Ⅲ)/Cu(Ⅱ) process. The reduction/oxidation potential values depend on the structures of complexes. Also, the antimicrobial activities of these complexes were determined against S. aureus, E. coli and B. subtilis. 相似文献
204.
一个新的噻二唑衍生物H2ADTZ与锰的二维聚合物的合成与晶体结构(英) 总被引:2,自引:0,他引:2
A new 1,3,4 thiadiazole-derivative ligand 2,5-(s-acetic acid) dimercapto-1,3,4 thiadiazole (H2ADTZ) and its one-dimensional manganese polymer Mn(ADTZ)·4H2O had been synthesized and structurally characterized by X-ray single crystal diffraction in this paper. The Mn(Ⅱ) ion is coordinated with a distorted octahedron by two oxygen atoms from neighboring two deprotonated ligands ADTZ2- and other four oxygen atoms from four coordinated water molecules. The structural feature of the title compound is the formation of one-dimensional manganese chains polymer through the bridging of dioxygen O-O units. In the solid state structure of the complex, one-dimensional manganese chains are joined together by the weak intermolecular hydrogen bonds and vander Waals interactions forming a two-dimensional supramolecular compound. Furthermore, the UV spectra and electro-chemical properties of the title compound were also investigated. CCDC: 260532. 相似文献
205.
新型四四硫富瓦烯环蕃的合成和性质 总被引:3,自引:0,他引:3
利用2,3-二(2-氰基乙硫基)-6,7-二烷硫基四硫富瓦烯在甲醇钠的作用下消除一个保护基团生成四硫富瓦烯单钠盐, 与1,4-二氯甲基苯反应, 形成“单桥”-双(四硫富瓦烯)衍生物, 生成的“单桥”-双(四硫富瓦烯)衍生物再次在甲醇钠的作用下消除剩下的保护基团, 形成“单桥”-双(四硫富瓦烯)衍生物二钠盐, 最后与二溴代烷反应形成新型四四硫富瓦烯环蕃, 并通过循环伏安法和化学氧化法分别对其氧化还原性质和紫外光谱进行了研究. 相似文献
206.
The reaction of fluorobenzene with urotropine in trifluoroacetic acid (TFAA) at high pressures and temperatures affords predominantly fluorobenzaldehydes andN-(fluorophenylmethyl)trifluoroacetamides. The yields of these products depend considerably on the reaction conditions. The rates of their formation have the maximum values at the momemt of the phase transition (PT) of TFAA. A new efficient cyclic (dynamic) regime is proposed for the synthesis at high pressures. The regime involves periodically occurring PT of the solvent. The change in the relative rate of product formation with the degree of fluorobenzene conversion is wave-like.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 319–323, February, 1995. 相似文献
207.
L. N. Novikova B. A. Mazurchik N. A. Ustynyuk S. V. Kukharenko V. V. Strelets 《Russian Chemical Bulletin》1994,43(2):299-303
New cationic complexes [(6-C13H10)Fe(5-Cp*)]PF6 and [(6-9-CH3-C13H9)Fe(5-Cp*)]PF6 were obtained by the reaction of Cp*Fe(CO)2Br with fluorene and 9-methylfluorene, respectively. Deprotonation of these complexes byt-BuOK in THF affords zwitter-ionic compounds (6-C13H9)Fe(5-Cp*) and (6-9-CH3-C13H8)Fe(5-Cp*) (A). WhenA is heated in nonane at 150 °C it undergoes 65 inter-ring rearrangement with the formation of hexamethyldibenzoferrocene (B). The electrochemical behavior ofA andB was studied by cyclic voltammetry. One-electron reduction ofA andB to the corresponding radical anions induces inter-ring haptotropic rearrangementA
.–B
.–. The equilibrium in the 19 state is shifted to the 6-isomeric radical anionA
.–, while in the 18 precursors, it shifts to the 5-isomerB.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 319–324, February, 1994.The authors are grateful to D. V. Zagorevskii (A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences) for recording and interpreting the mass spectra, and to A. A. Borisenko (Moscow State University) for recording the NMR spectra.This work was financially supported by the Russian Foundation for Basic Research (Grant 93-03-5209). 相似文献
208.
Efficient synthesis of cyclic -alkyl--dicarbonyl compounds of the cyclopentane, cyclohexane, tetronic acid, and -pyrone series from the corresponding cyclic -acyl--dicarbonyl compounds under the action of NaBH3(CN) in a THF--HCl system is described. 相似文献
209.
Tezuka Y 《Chemical record (New York, N.Y.)》2005,5(1):17-26
A collection of recent developments in topological polymer chemistry is presented. First, topological isomerism occurring on randomly coiled, flexible polymer molecules having cyclic and linear structures is discussed. Second, an electrostatic self-assembly and covalent fixation strategy has been developed for the synthesis of polymeric topological isomers. These isomers have double cyclic, manacle-, and theta-shaped constructions, and are prepared by using either linear or star telechelic polymer precursors having moderately strained cyclic ammonium salt groups, which carry multifunctional carboxylate counteranions. A technique of reversed-phase chromatography (RPC) is demonstrated as an effective means to separate polymers with different topologies, especially polymeric topological isomers. A further extension of topological polymer chemistry has been observed by dynamic selection from electrostatic polymer self-assembly to enable the effective formation of tadpole-shaped, cyclic-linear hybrid topologies. 相似文献
210.
A. V. Varlamov D. G. Grudinin A. I. Chernyshev A. N. Levov I. Yu. Lobanov R. S. Borisov F. I. Zubkov 《Russian Chemical Bulletin》2004,53(8):1711-1716
5-Methyl-4,5-dihydro-3H-spiro[benzo-2-azepine-3,1-cyclohexane] N-oxide was rear- ranged into 5-methyl-1-oxo-1,2,4,5-tetrahydro-3H-spiro[benzo-2-azepine-3,1-cyclohexane]. The latter was used for the synthesis of spiro{triazolo[3,4-a]- and-tetrazolo[5,1-a]benzo-2- azepinecyclohexanes}.Published in Russian in Izvestiya Akademii Nauk.
Seriya Khimicheskaya, No. 8, pp. 1647–1651, August, 2004. 相似文献