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191.
本文利用巯基化合物对异硫氰酸荧光素(FITC)的荧光猝灭作用,建立了一种快速检测巯基化合物的新方法。实验中发现,巯基化合物能够猝灭FITC的荧光,据此发展了检测巯基化合物的新方法。本方法的用时非常短,在优化了pH、反应时间等条件后能在5min之内完成对巯基化合物的检测。在最佳条件下对实际样品的测试取得了很好的效果,且具有良好的选择性。对谷胱甘肽(GSH)、高半胱氨酸(Hcy)、半胱氨酸(Cys)、二硫苏糖醇(DTT)的检测限分别达到3.08、2.66、1.28和1.92μmol/L。 相似文献
192.
193.
Lun Song Xu-Dong Sun Yu Ge Yu-Hua Yao Jie Shen Wei-Bing Zhang Jun-Hong Qian 《中国化学快报》2016,27(12):1776-1780
A polarity-sensitive fluorescent probe MNP was rationally designed and synthesized with naphthalimide as the fluorophore and maleimide as the receptor for thiols. MNP is weakly fluorescent due to the photoinduced electron-transfer(PET) from the fluorophore to the receptor, and it displays evidently solvatochromic UV–vis and fluorescence spectra: the emission shifted from 495 nm in n-hexane to545 nm in phosphate buffer solution. Michael addition reaction between thiols and the maleimide in MNP inhibited the PET process, which led to about eight-fold fluorescence enhancement. In addition,MNP showed highly sensitivity to mercapto-containing proteins and it could detect as low as 20.4 mg/m L of BSA in PBS. MNP has potential in fluorescent imaging of thiols in living cells. 相似文献
194.
Summary A high performance liquid chromatographic method has been developed for the determination of aliphatic thiol drugs, such as N-acetyl-L-cysteine, captopril and mercaptopropionylglycine in pharmaceutical formulations. The procedure involves a precolumn derivatization of the thiol drug with ethacrynic acid followed by reversedphase HPLC separation and UV detection. The conditions for a rapid and selective reaction of the thiols with ethacrynic acid have been investigated. The method proved to be suitable for a reliable and selective quality control of commercial dosage forms of the examined thiol drugs. 相似文献
195.
Xavier Moreau 《Journal of organometallic chemistry》2003,687(2):322-326
Palladium catalyzed cystein thiol cross-coupling reactions with aryl and vinyl halides have been investigated: Pd2dba3-CHCl3 and dppf are the key choice in these reactions. The role of the base in these reactions was also questioned: it has been shown that base can be replaced by an HX-scavenger such as propylene oxide. 相似文献
196.
Saburo Aimoto Kenta Teruya Koki Hasegawa Takeshi Sato Kenichi Akaji Toru Kawakami 《高等学校化学研究》2006,22(2):253-257
Introduction Theavailabilityofsite specificallymodifiedpep tidesisofvitalimportanceforbiochemicalandbiophys icalstudies.Biologicalmethods,suchasexpression usingbacteria,areuseful.Theyare,however,notal waysapplicabletothesynthesisofpeptideswithsite specifi… 相似文献
197.
The first convenient synthesis of 2-S-cysteinyl-3,4-dihydroxyphenylalanine (2-S-cysteinyldopa) in 30% overall yield is reported, which capitalizes on the anomalous regiochemistry of the oxidative coupling of 3,4-dihydroxycinnamic acid derivatives with thiol compounds, leading to 2-S rather than the usual 5-S conjugates. 相似文献
198.
Phenyl trifluorovinyl sulfide: a radical acceptor for preparation of gem-difluoromethylene compounds
Phenyl trifluorovinyl sulfide was prepared from the reaction of trifluorovinyllithium and S-phenyl benzenethiosulfonate. The fluorinated olefin showed reactivity with alkyl radicals generated from halogen-abstraction from alkyl halides. Reactions with alkyl halides required tris(trimethylsilyl)silane as a chain transfer reagent to improve selectivity of the products. Initiation of radical reaction was effected by thermal decomposition of AIBN. Oxidation of the thioether products gave the corresponding sulfoxides, which were successively converted into α,α-difluoroalkanecarboxylic acid thiol esters by Pummerer reaction. 相似文献
199.
The performance of preheated glassy carbon electrode modified with carbon nanotubes is described. First glassy carbon electrode is heated for 5 min at 50 °C, then abrasive immobilization of multiwall carbon nanotubes on a preheated glassy carbon electrode was achieved by gentle rubbing of electrode surface on a filter paper supporting carbon nanotubes. Carbon nanotubes (CNTs)-modified glassy carbon electrodes exhibit strong and stable electrocatalytic response toward thiols oxidation in wide pH range. These properties permit an important decrease in over voltage for the oxidation of thiocytosine, glutathione and l-cysteine, as well as a dramatic increase in the peak currents in comparison with bare glassy carbon electrode. Furthermore, the thiols amperometric response of the coated electrodes is extremely stable, with more than 95% of the initial activity after 30 min stirring of 0.1 mM thiols. The electrocatalytic behavior is further exploited as a sensitive detection scheme for thiols detection by hydrodynamic amperometry. The substantial decrease in the overvoltage of the thiols oxidation associated with a stable amperometric response and antifouling properties of nanotubes films allow the development of highly sensitive thiols sensor without using any redox mediator. Such ability of carbon nanotubes to promote the thiols electron transfer reaction, short response time (5 s) and long-term stability, low detection limit, extended linear concentration range, high sensitivity suggest great promise for thiols amperometric sensors and detector for chromatographic analysis of thiol derivatives. 相似文献
200.
Katrin Rößler Bernhard Walfort Rudolf Holze Heinrich Lang 《Journal of organometallic chemistry》2007,692(7):1530-1545
The synthesis of the biphenyl alkynyl thiols and thioesters R′-CC-C6H4-C6H4-SR (3: R′ = SiMe3, R = C(O)Me; 4: R′ = SiMe3, R = H; 5: R′ = H, R = C(O)Me) from I-C6H4-C6H4-SC(O)Me (1) is described. Molecules 1 and 5 have been used as starting materials in the synthesis of mono- and heterobimetallic transition metal complexes of type LnM′-CC-C6H4-C6H4-SR (7: LnM′ = Fc, R = C(O)Me; 8: LnM′ = Fc, R = H; 10: LnM′ = (Ph3P)Au, R = C(O)Me; 14: LnM′ = FcPPh2-Au, R = C(O)Me; Fc = (η5-C5H5)(η5-C5H4)Fe; FcPPh2 = (η5-C5H5)(η5-C5H4PPh2)Fe). While complex 7is accessible by the Sonogashira cross-coupling of Fc-CCH (6) with 1, molecules 10 and 14 can be prepared by treatment of the thioester 5 with (Ph3P)AuCl (9) and FcPPh2-AuCl (13), respectively.The molecular solid state structures of 3, 7, 10 and 13-15 have been determined by single crystal X-ray crystallographic analysis. Typical features of these species are their linear M-CC-C6H4-C6H4-SR structure and the lack of coplanarity of the biphenyl arene rings. The overall length of these complexes are 13.345(2) Å for 3 (molecule A), 15.146(3) Å for 7, 15.705(2) Å for 10 (molecule A) and 15.649(4) Å for 14. The thioester groups are pointing away from the ferrocene building block. In 7 a linear 1D chain is set-up by π-interactions between two independent molecules of 7. Characteristic for 15 is the formation of a Au2I2 ring, while 13 is monomeric.All compounds were studied with cyclic voltammetry. Characteristic are the reversible ferrocene Fe(II)/Fe(III) redox wave, the irreversible reduction of Au(I) to Au(0), the oxidative cleavage of the S-C(O)Me sulfur-carbon (3, 5, 7, 10 and 14) and of the sulfur-hydrogen bond (4 and 8), respectively. Electronic effects extending from the -SH-end group to the ferrocene unit resulting in considerable shifts of the redox potential of the latter entity are found. Coordination of Au(I) at the FcPPh2 moiety also results in a shift of the redox potential of the ferrocene group indicative of an electron withdrawing effect of the Au(I) species. 相似文献