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由香茅醛与盐酸羟胺在碳酸钠作用下反应制得香茅醛肟(2),再由香茅醛肟与溴代烷、氢氧化钠在四丁基溴化铵的作用下反应合成了4种香茅醛肟烷基醚,分别为香茅醛肟乙基醚(3a)和香茅醛肟正丙基醚(3b)、香茅醛肟正丁基醚(3c)和香茅醛肟正戊基醚(3d)。5个化合物经红外光谱(FT-IR)、核磁共振(1H NMR、13C NMR)、气质联用(GC-MS)分析表征了结构,并用菌丝生长速率法对11种植物病原真菌的抑制作用进行了测试。结构分析数据表明所用方法能合成得到5种目标化合物。在药液质量浓度为500 mg/L时,5种化合物对所用植物病原真菌均有一定的抑制作用,化合物2对水稻纹枯病菌的抑制率与百菌清一样高达100%,对辣椒菌核病菌、辣椒疫霉病菌、猕猴桃果实拟茎点霉菌、梨链格孢菌和毛竹枯梢病菌的抑制率高达100%,对油茶炭疽病菌、层出镰刀菌的抑制率也很高(≥95%),明显优于百菌清对这些病菌的抑制效果,3a对莴苣菌核病菌的抑制率高达100%,3b对葡萄炭疽病菌的抑制率为100%,3c对毛竹枯梢病菌的抑制率为87.7%,3d对莴苣菌核病菌的抑制率为96.2%,均高于同等质量浓度下百菌清对这些植物病原真菌的抑制率。 相似文献
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以香茅醛为原料,经二甲胺羰基保护、硫酸催化条件下甲氧基化、氢氧化钠中和合成甲氧基香茅醛。考察了反应温度、反应时间、投料比等工艺条件对产品收率的影响。实验研究得到了最优的合成工艺条件为:胺化反应二甲胺与香茅醛摩尔比为2∶1,反应温度10~15℃,反应时间3 h。甲氧基化反应硫酸浓度为100%,甲醇∶硫酸∶烯胺的摩尔比为15∶5∶1,反应温度15~18℃,反应时间2 h。产品总收率47.6%。反应工艺简单,条件温和,原料易得,便于工业化。产品经IR1、H NMR、GC/MS、元素分析确证结构。 相似文献
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Brett Boonen Justyna B. Startek Alina Milici Alejandro Lpez-Requena Melissa Beelen Patrick Callaerts Karel Talavera 《International journal of molecular sciences》2021,22(20)
Background: The transient receptor potential ankyrin 1 (TRPA1) cation channels function as broadly-tuned sensors of noxious chemicals in many species. Recent studies identified four functional TRPA1 isoforms in Drosophila melanogaster (dTRPA1(A) to (D)), but their responses to non-electrophilic chemicals are yet to be fully characterized. Methods: We determined the behavioral responses of adult flies to the mammalian TRPA1 non-electrophilic activators citronellal and menthol, and characterized the effects of these compounds on all four dTRPA1 channel isoforms using intracellular Ca2+ imaging and whole-cell patch-clamp recordings. Results: Wild type flies avoided citronellal and menthol in an olfactory test and this behavior was reduced in dTrpA1 mutant flies. Both compounds activate all dTRPA1 isoforms in the heterologous expression system HEK293T, with the following sensitivity series: dTRPA1(C) = dTRPA1(D) > dTRPA1(A) ≫ dTRPA1(B) for citronellal and dTRPA1(A) > dTRPA1(D) > dTRPA1(C) > dTRPA1(B) for menthol. Conclusions: dTrpA1 was required for the normal avoidance of Drosophila melanogaster towards citronellal and menthol. All dTRPA1 isoforms are activated by both compounds, but the dTRPA1(B) is consistently the least sensitive. We discuss how these findings may guide further studies on the physiological roles and the structural bases of chemical sensitivity of TRPA1 channels. 相似文献
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短程蒸馏因具有受热时间短、分离效率高和可保持物质天然活性等优势,被广泛用于食品添加剂的提纯和精制。准确预测产品分离纯度以及分离效率对短程蒸馏工艺参数优化和设备设计有重要的意义。本文利用短程蒸馏分离了香茅油中香茅醛,并基于Langmuir-Kundsen方程建立了多组分传质模型,模拟了分离过程,预测了不同工艺条件对香茅醛分离纯度以及分离效率的影响,模拟结果与实验数据存在较好的一致性。研究结果表明:香茅醛的分离集中在蒸发器的前段,在蒸发器一半位置(z/L=0.5),香茅醛分离效率已达最终分离效率的60%以上。提高进料量、降低蒸发温度或减小蒸发面积均有利于香茅醛的纯化,但会降低其分离效率。综合香茅醛分离纯度以及分离效率,获得最佳工艺条件为:进料量4~5 m L/min,温度65~70℃。 相似文献
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V. Satagopan Sampatraj B. Chandalia 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1994,60(1):17-21
The hydrogenation of cinnamaldehyde to cinnamyl alcohol over a platinum on carbon catalyst could be intensified and made more selective in a two-phase system using toluene and aqueous alkaline solution. Enhancement in the selectivity with respect to citronellol was noticed in the two-phase hydrogenation of citronellal, while the reaction rate was marginally affected. Potassium hydroxide and sodium hydroxide were found to be efficient promoters. 相似文献
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