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羰基化反应的若干开发研究进展 总被引:7,自引:0,他引:7
本文介绍了羰基化反应及其特点。指出在我国资源条件下, 开发作为现代化工骨干技术的羰基化反应具有重要的现实与战略意义。报道了国内外羰基化技术研究、开发的若干进展与现状, 对在我国发展羰基化技术提出了建议。 相似文献
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催化选择氧化还原羰基化合成脲* 总被引:2,自引:0,他引:2
本文概述了胺硝基物选择氧化还原羰基化生成脲的新工艺路线。对催化剂体系、羰基化反应机理和反应的选择性作了比较全面的评述,着重介绍了金属钯和非金属硒催化的选择氧化还原羰基化反应合成对称脲、非对称脲和环脲,讨论了该方法的应用前景。 相似文献
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由煤制乙炔经羰基化反应合成丙烯酸的研究进展 总被引:1,自引:0,他引:1
介绍了由煤制乙炔经羰基化反应合成丙烯酸的研究进展,包括丙烯酸的市场分析、合成工艺路线、催化剂筛选等。参考文献17篇。 相似文献
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The site-specific identification of α-aminoadipic semialdehyde (AAS) and γ-glutamic semialdehyde (GGS) residues in proteins is reported. Semialdehydic protein modifications result from the metal-catalyzed oxidation of Lys or Arg and Pro residues, respectively. Most of the analytical methods for the analysis of protein carbonylation measure change to the global level of carbonylation and fail to provide details regarding protein identity, site, and chemical nature of the carbonylation. In this work, we used a targeted approach, which combines chemical labeling, enrichment, and tandem mass spectrometric analysis, for the site-specific identification of AAS and GGS sites in proteins. The approach is applied to in vitro oxidized glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and an untreated biological sample, namely cardiac mitochondrial proteins. The analysis of GAPDH resulted in the site-specific identification of two AAA and four GGS residues. Computational evaluation of the identified AAS and GGS sites in GAPDH indicated that these sites are located in flexible regions, show high solvent accessibility values, and are in proximity with possible metal ion binding sites. The targeted proteomic analysis of semialdehydic modifications in cardiac mitochondria yielded nine AAS modification sites which were unambiguously assigned to distinct lysine residues in the following proteins: ATP/ATP translocase isoforms 1 and 2, ubiquinol cytochrome-c reductase core protein 2, and ATP synthase α-subunit. 相似文献
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HAO Maorong FENG Wenlin Jl Yongqiang & LEI MingFaculty of Science Beijing University of Chemical Engineering Beijing China Faculty of Chemical Engineering Ningxia University Yinchuan China 《中国科学B辑(英文版)》2004,47(1):41-49
In the reaction cycle for methanol carbonylation catalyzed by Rh complex, the structure geometries of the reactant, intermediates, transition states and product of each elemental reaction have been studied by using the energy gradient method at HF/LANL2DZ level, and the changes of their potential profiles have also been calculated. Through IRC analyses of the transition states for each elemental reaction, it is confirmed that the various structure geometries obtained are stationary points on the cycle reaction pathway of methanol carbonylation catalyzed by Rh complex, and the changes are given in energies and structure geometries of the reactant molecules along the reaction pathway of lowest energy. It has been proposed that the geometrical conversions of intermediates play an important role during the cycle reaction. Through analyses of structure geometries, it has been suggested that, in addition to cis- and trans-structure exchange linkage of catalysis reactive species, the two pathways, cis- and tra 相似文献
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Palmese A De Rosa C Marino G Amoresano A 《Rapid communications in mass spectrometry : RCM》2011,25(1):223-231
Carbonylation is a non-enzymatic irreversible post-translational modification. The adduction of carbonyl groups to proteins is due to the presence of excess of ROS in cells. Carbonylation of specific amino acid side chains is one of the most abundant consequences of oxidative stress; therefore, the determination of carbonyl groups content in proteins is regarded as a reliable way to estimate the cellular damage caused by oxidative stress. This paper reports a novel RIGhT (Reporter Ion Generating Tag) (A. Amoresano, G. Monti, C. Cirulli, G. Marino. Rapid Commun. Mass Spectrom. 2006, 20, 1400) approach for selective labeling of carbonyl groups in proteins using dansylhydrazide, coupled with selective analysis by bidimensional mass spectrometry. We first applied this approach to ribonuclease A and lysozyme as model proteins. According to the so-called 'gel-free procedures', the analysis is carried out at the level of peptides following tryptic digest of the whole protein mixture. Modified RNaseA was analyzed in combined MS(2) and MS(3) scan mode, to specifically select the dansylated species taking advantage of the dansyl-specific fragmentation pathways. This combination allowed us to obtain a significant increase in signal/noise ratio and a significant increase in sensitivity of analysis, due to the reduction of duty cycle of the mass spectrometer. The unique signal obtained was correlated to peptide 1-10 of RNaseA carbonylated and labeled by dansylhydrazide. This strategy represents the first method leading to the direct identification of the carbonylation sites in proteins, thus indicating the feasibility of this strategy to investigate protein carbonylation in a proteomic approach. 相似文献
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Palladium-Catalyzed Low Pressure Carbonylation of Allylic Alcohols by Catalytic Anhydride Activation
Dr. Mathias Schelwies Dr. Rocco Paciello Dr. Ralf Pelzer Dr. Wolfgang Siegel Dr. Michael Breuer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(36):9263-9266
A direct carbonylation of allylic alcohols has been realized for the first time with high catalyst activity at low pressure of CO (10 bar). The procedure is described in detail for the carbonylation of E-nerolidol, an important step in a new BASF-route to (−)-ambrox. Key to high activities in the allylic alcohol carbonylation is the finding that catalytic amounts of carboxylic anhydride activate the substrate and are constantly regenerated with carbon monoxide under the reaction conditions. The identified reaction conditions are transferrable to other substrates as well. 相似文献
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硒催化的乙二胺、乙醇胺和环胺的氧化羰基化反应 总被引:3,自引:0,他引:3
研究了以硒粉作催化剂,一氧化碳为羰基化试剂的乙二胺、乙醇胺和一些环胺的羰基化反应,考察了氧化剂对反应的影响。发现氧气是该反应较好的氧化剂,而没有氧化剂存在时,几乎没有羰基化反应发生。在硒/氧化剂体系存在下,乙二胺和乙醇胺这样一些分子内具有相邻两个亲基团物质的羰基化反应易趋向于分子内羰基化形成较为稳定的五元环产物,产率和选择性较高;而环胺如哌啶和吗啡啉的羰基化可生成相应的四取代脲产物。对反应机理进行 相似文献
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Chatani N Fukuyama T Tatamidani H Kakiuchi F Murai S 《The Journal of organic chemistry》2000,65(13):4039-4047
The ruthenium-catalyzed carbonylation at the C-H bond of five-membered N-heteroaromatic compounds is described. The reaction of imidazoles with CO and olefins in toluene in the presence of a catalytic amount of Ru(3)(CO)(12) results in carbonylation of the C-H bond at the 4-position (adjacent to the sp(2)-nitrogen) of the imidazole ring to give acylated imidazoles in good to high yields. A wide range of olefins can be utilized in the carbonylation reaction, and a variety of functional groups are compatible under the reaction conditions. Other five-membered N-heteroaromatic compounds, such as pyrazoles, oxazoles, and thiazoles, can also be used for the carbonylation reaction, and in all cases, carbonylation takes place exclusively at a C-H bond alpha to the sp(2) nitrogen. The reactivity of the five-membered heterocycles corresponds to the pK(a) of the conjugate acid of these heterocycles. The higher the pK(a) of the substrate, the higher is the reactivity. This indicates that the pK(a) values are related to the ability of the nitrogen atom in the substrates to coordinate to a ruthenium center. The coordination of the substrates to the ruthenium center in the catalyst complex is a necessary prerequisite for the carbonylation to proceed. 相似文献
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Kostal V Levar K Swift M Skillrud E Chapman M Thompson LV Arriaga EA 《Analytical and bioanalytical chemistry》2011,400(1):213-222
The level of carbonylation in skeletal muscle is a marker of oxidative damage associated with disease and aging. While immunofluorescence
microscopy is an elegant method to identify carbonylation sites in muscle cross-sections, imaging analysis is manual, tedious,
and time consuming, especially when the goal is to characterize carbonyl contents in subcellular regions. In this paper, we
present a semi-automated method for the analysis of carbonylation in subcellular regions of skeletal muscle cross-sections
visualized with dual fluorescent immunohistochemistry. Carbonyls were visualized by their reaction with 2,4-dinitrophenylhydrazine
(DNPH) followed by immunolabeling with an Alexa488-tagged anti-DNP antibody. Mitochondria were probed with an anti-COXI primary
antibody followed by the labeling with an Alexa568-tagged secondary antibody. After imaging, muscle fibers were individually
analyzed using a custom-designed, lab-written, computer-aided procedure to measure carbonylation levels in subsarcolemmal
and interfibrillar mitochondrial regions, and in the cytoplasmic and extracellular regions. Using this procedure, we were
able to decrease the time necessary for the analysis of a single muscle fiber from 45 min to about 1 min. The procedure was
tested by four independent analysts and found to be independent on inter-person and intra-person variations. This procedure
will help increase highly needed throughput in muscle studies related to ageing, disease, physical performance, and inactivity
that use carbonyl levels as markers of oxidative damage. 相似文献
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以非金属硒作为催化剂,以CO替代剧毒光气作为羰基化试剂,以O2作为氧化剂,通过2-氨基-1,3,4-噻二唑与醇以"一锅法"方式发生硒催化氧化羰基化反应,提出了一种成本低、原子经济性高、合成路线简短及环境相对友好的合成1,3,4-噻二唑-2-氨基甲酸酯类化合物的新方法.研究了反应温度、醇的用量、压力及碱的种类等对合成1,3,4-噻二唑-2-氨基甲酸酯的影响,在优化反应条件下,2-氨基-1,3,4-噻二唑可与一系列醇顺利发生羰基化反应,以45%~90%的收率得到1,3,4-噻二唑-2-氨基甲酸酯类化合物. 相似文献