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报道了甲酸氧化态四氢叶酸辅酶模型--碘化-2,3-二甲基-1-对氯苯磺酰基咪唑啉的合成以及该模型化合物与双中心亲核试剂(乙二胺、邻苯二胺、邻氨基苯酚)的反应。结果表明,该化学模型具有较高的反应活性,能够实现甲基取代的一碳单元的彻底转移。 相似文献
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以甲酸铵为氢源和氮源,N,N-二甲基甲酰胺为溶剂,探讨了甲酸铵直接还原胺化乙酰丙酸制备5-甲基-2-吡咯烷酮的反应途径及机理。通过实验分别考察了反应温度、反应时间、乙酰丙酸与甲酸铵的总质量分数和物质的量比、体系pH值等反应条件对5-甲基-2-吡咯烷酮得率的影响趋势。结果表明,适当提高反应温度、延长反应时间、提高乙酰丙酸与甲酸铵的物质的量比和总质量分数、增加体系pH值均有利于提高5-甲基-2-吡咯烷酮的得率。同时,考察了不同溶剂和乙酰丙酸衍生物在该反应体系中的应用,结果表明极性非质子溶剂甲酰胺、N,N-二甲基乙酰胺、二甲亚砜亦可作为该中体系反应的反应溶剂,乙酰丙酸甲酯、α-当归内酯可作为反应底物在该体系下制备5-甲基-2-吡咯烷酮。 相似文献
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本文报道了(4-羟基-3-甲氧基苯基)(2-甲基哌啶-1-基)甲酮(1a)的合成。以4-羟基-3-甲氧基苯甲酸(2)和2-甲基哌啶(3)为原料,经缩合反应得到目标化合物(1a)。并考察该反应工艺,确定适宜的反应条件为:物料比为n(3)∶n(2)=1.8∶1、反应溶剂为N,N-二甲基甲酰胺、反应温度为40℃、反应时间为2h。在该条件下,产物(1a)收率达到88.6%。对该反应工艺的拓展应用发现,该条件同样适用于4-羟基-N,3-二甲氧基-N-甲基苯甲酰胺(1b)的合成,收率达到90.3%。产物结构经过1H NMR和13C NMR表征确证。 相似文献
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由3-羟基丙腈与叠氮化铵采用超声波辐射技术经1,3-偶极环化加成获得母体化合物5-羟乙基四唑;母体化合物与硫酸二甲酯经取代反应得到中间体甲基-5-羟乙基四唑,然后甲基-5-羟乙基四唑再与氯化亚砜经卤代反应得到中间体2-甲基-5-氯乙基四唑,收率为68%;2-甲基-5-氯乙基四唑在碱性条件下经消除反应生成2-甲基-5-乙烯基四唑,收率为75%。采用红外光谱、核磁共振、元素分析等对2-甲基-5-氯乙基四唑、2-甲基-5-乙烯基四唑进行了结构表征。该法具有反应收率较高且稳定、易操作等优点。 相似文献
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初步总结设计了一条4-甲基-7-芳基-2,1,3-苯并噻二唑的合成工艺路线,以3-甲基苯二胺为起始原料,分子内合环得到4-甲基-2,1,3-苯并噻二唑,再经溴代反应得到4-甲基-7-溴-2,1,3-苯并噻二唑,再与芳基硼酸发生Suzuki偶联反应得到4-甲基-7-芳基-2,1,3-苯并噻二唑。该方法采用廉价的3-甲基苯二胺为起始原料制取价格昂贵的2,1,3-苯并噻二唑4,7位取代产物,使得工艺更为廉价、简洁。该产物可作为许多光电材料的前体物质,为材料领域拓展了新的合成路线。 相似文献
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以13X沸石原粉为主要成分添加不同配比硅溶胶配制新型制冷复合吸附剂,采用热排空法对配制的复合吸附剂进行闭式吸附和脱附性能试验。用开放式吸附测量法对复合吸附剂的最大吸附量进行测试,同时测量各复合吸附剂填充密度以及整体成型性能与硅溶胶含量的变化。试验结果表明:复合吸附剂E的闭式吸附和脱附性能均优于13X沸石原粉;在封闭系统中复合吸附剂吸附速度远远高于在开放式系统;在硅溶胶含量0-7%时复合吸附剂的填充密度随添加的硅溶胶迅速下降。综合各性能参数,复合吸附剂E被选择应用于太阳能冷管,其制冷系数COP约为0.24-0.28。 相似文献
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In this work, a microhydrodynamic approach is used to investigate the motion of the meniscus on a vapor—liquid interface in narrow slitlike pores. Calculations are performed on the basis of Navier—Stokes—type equations, in which the transport coefficients and equation of state for a compound are calculated within the simplest molecular model of a gas lattice that takes into account the inherent volume of molecules and their interaction with each other and the pore wall. The dynamic modes of the flow of a liquid monatomic gas (argon) bearing a vapor bubble through nanosized pores at a given pressure difference across the pore are studied. The differences in the average rates of the liquid and vapor-bubble motion in a quasi-stationary regime caused by the intensive nonequilibrium processes of molecule exchange on the liquid—vapor and vapor—liquid boundaries, i.e., by the phase transitions on both boundaries of a bubble, are revealed. 相似文献
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Audrey Holes Alexandra Eusebi Daniel Grosjean David T. Allen 《Aerosol science and technology》2013,47(6):516-526
ABSTRACT The composition of aerosol generated in the photooxidation of 1,3,5-trimethylbenzene was investigated in a smog chamber experiment. The relative concentrations of alcohols, carboxylic acids, organonitrates, carbonyl groups, nitroaromatics, aliphatic C—H and aromatic C—H in the aerosol were estimated through analysis of infrared spectra. Based on model compound calibrations it was estimated that a typical molecule in the aerosol contained three carbonyl groups, six aliphatic C—H bonds, and one hydroxyl group. Small amounts of organic acids (one molecule in ten) and organonitrates (one molecule in four) were observed. About 5–10 wt% of the aerosol mixture was aromatic and these structures contained nitro and hydroxyl groups. This information on aerosol chemical functionality was coupled with gas-phase chemistry mechanisms to propose potential aerosol formation pathways. 相似文献
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文章采用微电解—ClO2催化氧化—生化复合废水处理技术对农药废水进行处理,研究表明:进水平均CODCr6000mg/L、色度1500倍时,经微电解—ClO2催化氧化—生化法复合处理后,出水CODCr为60mg/L、色度为15倍,CODCr去除率达99%,各项指标均能达标排放。因此,微电解—ClO2催化氧化—生化复合废水处理技术对农药中硝基和胺基废水处理效果较理想。 相似文献
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A Synthetic Transcriptional Activator of Genes Associated with the Retina in Human Dermal Fibroblasts
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Junetha Syed Anandhakumar Chandran Dr. Ganesh N. Pandian Junichi Taniguchi Shinsuke Sato Kaori Hashiya Dr. Gengo Kashiwazaki Dr. Toshikazu Bando Prof. Hiroshi Sugiyama 《Chembiochem : a European journal of chemical biology》2015,16(10):1497-1501
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The study of polymer interfaces is of prime importance in the field of tyre technology due to the critical role these contribute to tyre operation. The paper reviews the main polymer interfaces present in a tyre—(1) tyre/road (tyre wear or abrasion; tyre traction/skid resistance); (2) polymer/filler (carbon black; silica); (3) polymer/cord (brass coated steel wire; textile—rayon, nylon, polyester, aramid); (4) compound/compound (tack); (5) tyre/air (oxygen/ozone protection)—with respect to the criteria required, physical and chemical, to achieve optimum performance. 相似文献