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31.
32.
在四氯化碳中合成邻硝基对甲基苯胺的研究 总被引:3,自引:0,他引:3
以对甲基苯胺为母体,合成了邻硝基对甲苯胺,产品收率在85%以上,在乙酰化,硝化反应中引入了四氯化碳溶剂,2最佳原料配比为对甲基苯胺;醋酐:硫酸=1:1.30:1.13。改进后,每mol母体的醋酐用量由3.10mol减少至1.30mol,浓硫酸用量由3.17mol减少至1.13mol,溶剂回收率在95%以上。 相似文献
33.
Roger M. Rowell 《化学与化工:英文版》2013,(9):834-841
Many of the traditional woods used for musical instruments have been selected not only for their natural beauty but for the high content of waxes and resins that help increase water repellency of the wood but have little or no effect on stabilizing dimensions or vibrational properties. Moisture changes have a great negative effect on both the musical quality of wooden musical instruments and limit the length of time they can be played without loss of musical quality. It is possible to stabilize both the wood and the vibrational properties by chemically modifying the wood. One technology that can do this is the reaction of wood with acetic anhydride. Acetylation of wood slightly increases density, and slightly (about 5%) reduces both sound velocity and sound absorption when compared to unreactedwood. Acetylation does not change the acoustic converting efficiency. Acetylation reduces the amount of moisture in the cell wall decreasing the effect of moisture on the viscose properties of wood. This allows a wooded musical instrument to be played longer without having to let it dry out. This gives an instrument made from acetylated wood a greater range of moisture conditions it can be played in without losing tone quality. Acetylation also greatly stabilizes the physical dimensions of the wood. The major effect of acetylation of wood, therefore, is to stabilize acoustic properties. The technology can be applied to almost any wood though more easily to permeable types so non-traditional wood species can be used. A violin, a piano soundboard, a guitar, a recorder, a bagpipe chanter, and trumpet and trombone mouthpieces have been made using acetylated wood with very positive results. Several more wooden instruments made from acetylated wood are presently being made for further testing and early market development. 相似文献
34.
目的:从组蛋白乙酰化修饰角度探讨姜黄素上调乳腺癌MCF-7和MCF-7/DOX细胞中多药耐药基因1(multidrug resistance protein 1,MDR1)表达水平的作用机制。方法: CCK-8(Cell Counting Kit-8)法观察姜黄素对MCF-7和MCF-7/DOX细胞生长增殖以及多柔比星敏感性的影响;Real time PCR和Western blot方法检测姜黄素处理前后两种细胞中MDR1 mRNA和蛋白质表达水平的变化;染色质免疫共沉淀技术(chromatin immunoprecipitation assay,CHIP)检测姜黄素对两种细胞中MDR1启动子区相关组蛋白H3、H4乙酰化水平的影响。结果: 不同浓度姜黄素处理72 h对MCF-7和MCF-7/DOX细胞的生长增殖有显著抑制作用,其IC50值分别为22.03 μmol/L和27.46 μmol/L;10 μmol/L姜黄素处理72 h可显著提高两种细胞多柔比星敏感性,多柔比星IC50值分别下降了57.14%和54.52%(P<0.05);姜黄素处理MCF-7和MCF-7/DOX细胞后,MDR1在mRNA水平分别上调(32.90±0.96)和(5.70±0.55)倍(P<0.05),在蛋白质水平分别上调(2.26±0.18)与(2.90±0.21)倍(P<0.05);CHIP结果显示姜黄素对两种细胞中MDR1启动子区相关组蛋白H3、H4的乙酰化水平均有显著上调作用。结论:姜黄素在增强MCF-7和MCF-7/DOX细胞多柔比星敏感性的同时,可通过调控MDR1启动子区相关组蛋白H3、H4的乙酰化水平而上调MDR1的表达。 相似文献
35.
以苯和丙酸为起始原料,经酰氯化、Freidel-Crafts酰基化和沃尔夫-克斯尼尔-黄鸣龙还原反应合成了正丙苯。采用1H NMR方法分析了产物结构。表征结果显示,中间产物及最终产物为目标化合物。考察了反应物的摩尔比、反应温度和反应时间对各反应的影响。实验结果表明,合成中间产物丙酰氯、苯丙酮和最终产物正丙苯的各反应的优化条件分别为:n(氯化亚砜)∶n(丙酸)=1∶1.1,120℃反应6 h;n(丙酰氯)∶n(AlCl3)∶n(苯)=1∶1.1∶8.5,50℃反应2 h,80℃反应4 h;n(苯丙酮)∶n(水合肼)∶n(KOH)=1∶4∶2,120℃反应2 h,160℃反应4 h。在优化的反应条件下,丙酰氯、苯丙酮和正丙苯的收率分别可达73.5%,90.1%,95.6%。 相似文献
36.
José A. Souto Dr. Rosaria Benedetti Katharina Otto Marco Miceli Rosana Álvarez Prof. Dr. Lucia Altucci Prof. Dr. Angel R. de Lera Prof. Dr. 《ChemMedChem》2010,5(9):1530-1540
A series of N‐(4‐cyano‐3‐trifluoromethyl‐phenyl)‐2‐ethoxy‐6‐alkyl (and alkenyl) benzamides related to the anacardic acid derivative CTPB have been prepared from 2,6‐dihydroxybenzoic acid with a Suzuki coupling and addition of the anion of 4‐cyano‐3‐trifluoromethylphenylamine to a benzodioxinone as the key steps. In U937 cells, these analogues, in particular 7 c , 7 d , 7 f and 7 j , induced cell‐cycle arrest in the G1 phase, caused apoptosis in about 20 % of the cells, and increased the acetylation levels of H3. These activities correlate with the enzymatic activation of histone lysine acetyltransferases (KATs): CBP and PCAF. 相似文献
37.
Indu Bhushan Anil Kumar Gourav Modi Subika Jamwal 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(2):315-318
In the present investigation a Lipase producing strain, Bacillus subtilis (MTCC‐121) was grown on various media containing different sources of carbon, nitrogen and other nutrients. The best media found for the production of lipase was M2 media containing 0.4% peptone, 0.2% beef extract and 1% NaCl. Lipase produced from this culture was used for the kinetic resolution of racemic acetyl‐1‐phenyl ethanol and its derivatives, which are important as chiral auxiliaries and intermediates in the synthesis of natural products, pharmaceuticals and agrochemicals. The lipase resolved these substrates after 48 h with enantiomeric excess of 90–98% and conversion 40–48%. Copyright © 2010 Society of Chemical Industry 相似文献
38.
在熔融状态下,利用无水AlCl3引发大分子之间的Friedel-Crafts烷基化反应来增容聚苯乙烯(PS)/线性低密度聚乙烯(LLDPE)(80/20)合金。研究了"一步法"和"两步法"增容工艺对PS/LLDPE合金结构和性能的影响。结果表明,以"一步法"增容PS/LLDPE(50/50)合金40份为母料,与60份聚苯乙烯混合("两步法")制备PS/LLDPE(80/20)合金,可有效地降低聚苯乙烯降解对合金性能的影响,提高合金的热稳定性和力学性能;从扫描电镜(SEM)照片可以看出,"两步法"制备的合金的分散相更加均匀细小,韧性断裂特征明显。 相似文献
39.
Michela Signoretto Antonella Torchiaro Anna Breda Francesco Pinna Giuseppina Cerrato Claudio Morterra 《Applied catalysis. B, Environmental》2008,84(3-4):363-371
A series of sulphated zirconia samples (SZ) promoted with Al2O3, Ga2O3, and Fe2O3 were synthesized by co-precipitation at constant pH and aged under reflux conditions. Structural, surface and catalytic properties of the samples were investigated using N2 adsorption/desorption, thermal analysis, in-situ FTIR spectroscopy, TPR–MS and EGA–MS measurements. The catalytic performance of promoted SZ in anisole acylation has been investigated. Promotion by either Fe2O3 or Ga2O3 was found to increase the catalytic activity (yield) after recycle of catalysts with respect un-promoted sample, whereas promotion by Al2O3 was observed to increase the conversion but not the yield. It is worth noting that all systems present high selectivity to the p-metoxyacetophenone product. 相似文献
40.