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21.
22.
Nadine Metz 《European Polymer Journal》2007,43(4):1202-1209
Acetone oxime acrylate has been synthesized as a new active ester monomer. Free radical polymerization yielded a reactive polymer soluble in various organic solvents, such as chloroform, dioxane, DMSO, acetone, methanol, dichloromethane, DMF, and ethanol. Controlled radical polymerization of acetone oxime acrylate was successfully conducted using the RAFT, NMP and Iniferter method. Partly polymer analogous reaction with N-isopropylamine resulted in the reactive copolymer poly(N-isopropylacrylamide-co-acetone oxime acrylate), which featured a lower critical solution temperature (LCST) of 61 °C in water. Further, the reactivity of the copolymer was exemplary proven by complete reaction with ammonia yielding poly(N-isopropylacrylamide-co-acrylamide), which does not possess a LCST. 相似文献
23.
蔗糖酯分子在碱性条件下,加热水解为蔗糖和硬酯酸,在pH>10的NH_3·N_2O-(NH_3)_3C_6H_5O_7体系中,于示波极谱仪上,峰电位─0.91V处出现一灵敏度高和稳定性好的极谱图,其浓度从0.02~0.28mg/mL与峰电流呈线性关系,最低检出限为0.004mg/mL,相对标准偏差为1.3%。 相似文献
24.
Zur Synthese von fungizid wirksamen Isocamphanderivaten: Synthesen in der Isocamphanreihe, 34. Mitt.
Gerhard Buchbauer Helmut Spreitzer Margarete Kneidinger 《Monatshefte für Chemie / Chemical Monthly》1990,121(6-7):549-554
Summary Some esters of isocamphenilanic acid (4) have been prepared and tested for their fungicidal and insecticidal activity. Esters of various acids with isocamphanyl ethylalcohol (5) have also been synthesized and included in the fungicidal/acaricidal/insecticidal screening programme. All esters bear a geminal dimethyl group at C-3 of the bicyclus which is important because of its shielding effect. 相似文献
25.
为增强有机锗化合物的生物活性,合成了一系列有机锗氨基酸酯类倍半氧化物,并重点研究了它们的快原子轰击质谱(FABMS)。研究结果表明:该系列化合物的各碎片离子峰与其组成及结构均有很好的对应关系及很强的规律性 相似文献
26.
Clinical applications of chemiluminescence 总被引:8,自引:0,他引:8
This article reviews the clinical applications of chemiluminescence in routine testing and surveys the diverse applications of chemiluminescence in clinical research. In routine clinical testing, chemiluminescent labels (acridinium ester, acridinium sulfonamide) and detection reactions for peroxidase and alkaline phosphatase enzyme labels (luminol and adamantyl 1,2-dioxetane-based reactions, respectively) are widely used in immunoassay and nucleic acid probe assays (e.g. hybridization protection assay, Hybrid Capture® assay). In clinical research the sensitivity, dynamic range and diversity of chemiluminescent assays has led to a vast range of applications, notably in protein and nucleic acid blotting, microarray-based assays, monitoring reactive oxygen species, and as detection reactions for substances separated by HPLC, capillary electrophoresis (CE), and flow-injection analysis. 相似文献
27.
Acyclic nitrones react with dimethyl acetylenedicarboxylate (DMAD) to give stable isoxazolines, from which the ones that contain electron-donating aromatic rings at the C3 position (R1) were shown to undergo unprecedented fragmentation at room temperature, giving the R1-aldehyde and inseparable product mixtures, probably due to the formation of highly reactive species such as iminocarbenes. Attempts to convert the isoxazolines to the corresponding stable azomethine ylides, by refluxing in toluene, again led to the same product mixtures as above (e.g., the room temperature decomposition). Isoxazolines when reacted with methoxide at room temperature afforded highly functionalised diastereomeric mixtures. Also, isoxazolines, when reacted with propylamine, gave the corresponding amides regioselectively, all of which were more stable than the parent isoxazolines. 相似文献
28.
N-Acyl-β-hydroxy-4-phenyl-oxazolidinethiones could be rapidly converted into their ethyl thiol esters in high yields by treatment with EtSH at 0 ℃ in CH3CN or 9 : 1 (V : V) THF-H2O in the presence of a catalytic amount of K2CO3. 相似文献
29.
用上升液滴法测定了2-乙基己基膦酸单(2-乙基己基)酯-正辛烷从硝酸介质中萃取镁、钙、锌、镍、铜和铅等二价金属离子的正向初始速率,建立了速率方程,计算出正向萃取反应的速率常数、活化能及活化熵,首次将软硬酸碱规则与金属溶萃取速率常数关联。结果表明,在萃取机理相同时,萃取速率常数的大小与金属离子的软硬酸碱标度一致,即萃取过程中,作为酸的被萃取金属离子,其硬度越大,萃取速率常数亦越大,萃取反应的活化能… 相似文献
30.
An enantioselective synthesis of (+)-prelactone B 1 has been achieved on a multigram scale starting from a known bicyclic precursor 2. The key feature of the strategy is the generation of 3-stereogenic centres from a single bicyclic precursor, which has been utilized as a chiral building block for the synthesis of various natural products. 相似文献