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81.
莫达非尼的绿色化学合成 总被引:1,自引:0,他引:1
采用[bm im]BF4离子液体作为反应溶剂,以二苯甲硫醇为原料,经醚化、氨解、氧化得到新型提神醒脑药物莫达非尼。讨论了不同的氯乙酸酯和反应温度对醚化反应收率的影响,讨论了不同的二苯甲硫乙酸酯对氨解反应收率的影响,及离子液体的回收使用。研究表明,采用氯乙酸甲酯作为醚化试剂,反应时间4 h,反应温度100℃,二苯甲硫醇∶氯乙酸甲酯=1∶1.5(摩尔比),室温下氨解反应20 h,二苯甲硫乙酰胺收率76%;采用过氧化氢作为氧化试剂,反应时间3 h,反应温度60℃,过氧化氢∶二苯甲硫乙酰胺=1∶1(摩尔比),莫达非尼收率79%,反应总收率可达48%。 相似文献
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The pheromone system of the summer fruit tortrix mothAdoxophyes orana (Fischer von Röslerstamm) consists of a mixture ofcis-9- andcis-11-tetradecen-1-ol acetate (cis-9- andcis-11-TDA, respectively) in a ratio of 9:1. Substitution of one or both of these compounds by related unsaturated acetates reduced the attractancy. Onlycis-11-TDA could be replaced bycis-11-tridecen-1-ol acetate (cis-11-TriDA), although the 9:1 mixture ofcis-9-TDA andcis-11-TriDA was less attractive in the field than the pheromone system itself. The major component of the pheromone system of the leaf rollerClepsis spectrana (Treitschke)(cis-9-TDA:cis-11-TDA=1:9) could also be replaced bycis-11-TriDA, again with some reduction in attractancy. 相似文献
84.
Ragnar Larsson 《Catalysis Letters》1991,10(3-4):317-324
Kinetic data on the exchange reaction betwee hexane and deuterium have recently been reported by Maier and coworkers [1]. The reaction was catalysed by a series of platinum or rhodium systems, some of which had the property that the upper surface was shielded by a silica overlayer. The data are reinterpreted to indicate an isokinetic temperature of 580 K. This observation indicates that all the catalysts behave in a similar manner, which means that the exchange reaction does not require a free metal surface. 相似文献
85.
介绍理想气体、理想气体混合物、真实气体、真实气体混合物的有效能计算方法,并以硫酸工业中常见气体为例加以说明。通过编写计算机程序进行计算,可实现有效能的快速分析,便于实际应用。 相似文献
86.
Hiromi Yoshida Mikiko Tatsumi Goro Kajimoto 《Journal of the American Oil Chemists' Society》1991,68(8):566-570
Effects of microwave heating on the oxidative stability ofd-tocopherols were studied in relation to the production of fatty acids in oils. During microwave heating, the stability of
tocopherols decreased in the orderδ>β>γ>α. This order did not depend on the types of ethyl esters of fatty acids or oils present. But, the shorter the chainlength
and the lower the degree of unsaturation of the fatty acid ethyl esters, the greater was the reduction in amount of individual
tocopherols. A similar tendency was observed when tocopherol-stripped vegetable oils, with equimolar mixtures of tocopherols
added, were treated under the same conditions. The reduction in tocopherols became greater with increasing levels of free
fatty acids. 相似文献
87.
MaleArchips argyrospilus (Walker) were maximally attracted to a 60404200 admixture of (Z)-11-tetradecenyl, (E)-11-tetradecenyl, (Z)-9-tetradecenyl and dodecyl acetates. The identification of (Z)-9-tetradecenyl acetate, in addition to the other 3 components reported previously, is the first report of a 4-component pheromone system in moths.Archips mortuanus Kearfoot, a sibling species, was maximally attracted to a blend of the same components, but in a 90101 mix of the tetradecenyl acetates. Among a number of tortricine moths that co-occur on apples and other hosts in New York, British Columbia, and elsewhere, differences in diel rhythms of attraction and seasonal distribution are insufficient to maintain reproductive isolation. Although the attractant systems of these species often possess components in common, males are maximally attracted to a speciesspecific blend. In tortricine moths attraction specificity appears to be a paramount mechanism for species partitioning. 相似文献
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