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1.
高超  刘福胜 《应用化工》2014,(6):1086-1088,1092
以吗啉和一氯化硫为原料,以固体氢氧化钠为缚酸剂合成了N,N’-二硫代二吗啉(DTDM),考察了反应条件和重结晶条件对产物收率的影响。结果表明,较佳的合成工艺条件为:n(吗啉)∶n(S2Cl2)∶n(NaOH)=2∶1∶2,反应温度30~40℃,反应时间8 h,粗产品收率可达93%;较佳的重结晶工艺条件为:溶剂乙酸乙酯,m(溶剂)∶m(产品)=4∶1,结晶温度0~5℃,重结晶收率可达93%,DTDM总收率可达86%以上,采用FTIR与1H NMR对产物结构进行了表征。  相似文献   
2.
The general blueprint for the design of monoamine oxidase-B (MAO-B) inhibitors has been based on two phenyl or heteronuclei linked via a spacer of appropriate length. In this study, 1-[4-(morpholin-4-yl)phenyl]-5-phenylpenta-2,4-dien-1-one (MO10) was prepared by the condensation of 4′-morpholinoacetophenone and cinnamaldehyde in basic alcoholic medium. MO10 was assessed for inhibitory activity against two human MAO isoforms, MAO-A and MAO-B. Interestingly, MO10 showed a remarkable inhibition against MAO-B with an IC50 value of 0.044 μM along with a selectivity index of 366.13. The IC50 value was better than that of lazabemide (IC50 value of 0.063 μM), which was used as a reference. Kinetics studies revealed that MO10 acted as a competitive inhibitor of MAO-B, with a Ki value of 0.0080 μM. The observation of recovery of MAO-B inhibition, compared to reference levels showed MO10 to be a reversible inhibitor. MTT assays showed that MO10 was nontoxic to normal VERO cells with an IC50 value of 195.44 μg/mL. SwissADME predicted that MO10 provided advantageous pharmacokinetics profiles for developing agents acting on the central nervous system, that is, high passive human gastrointestinal absorption and blood–brain barrier permeability. Molecular docking simulations showed that MO10 properly entered the aromatic cage formed by Y435, Y398, and FAD of the active site of MAO-B. On the basis of these results, MO10 can be considered a promising starting compound in development of agents for the treatment of various neurodegenerative disorders.  相似文献   
3.
4.
以吗啉和丙烯腈为原料,经加成、催化加氢和精制过程生产N-氨丙基吗啉,考察了催化剂种类及用量、原料配比、反应温度、压力、时间等因素对反应的影响,确定了最佳工艺条件为n(丙烯腈)∶n(吗啉)=1.0∶1.05,反应温度40℃,反应时间5~5.5h,加成收率99%以上,精制后中间产物质量分数99%;采用粉末金属钴为催化剂,w(催化剂)=2%,质量分数25%氨水为助催化剂,w(助催化剂)=50%,反应温度150℃,反应压力4.0 MPa,反应5h,加氢收率88%以上,精制后产品质量分数99.7%。  相似文献   
5.
Morpholine basic ionic liquid was synthesized with N-methyl morpholine, N-butyl bromide, and KOH by two-step method and was used to catalyze the transesterification of soybean oil with methanol to biodiesel. The structure of the catalyst were examined by 1H nuclear magnetic resonance. The effects of the molar ratio of methanol to oil, reaction temperature, and amount of catalyst on the biodiesel yield were investigated. Optimized biodiesel yield of 94.5% was achieved with catalyst amount of 3.0 wt%, and methanol to soybean oil molar ratio of 14:1 at reaction temperature of 60 °C for 6 h. The catalyst has maintained sustained activity after being employed to six cycles. The prepared biodiesel component was analyzed by gas chromatography-mass spectrometry (GC-MS) and the results showed that the biodiesel comprised of hexadecanoic acid methyl ester, 10, 13-octadecadienoic acid methyl ester, 9-octadecenoic acid methyl ester, and octadecanoic acid methyl ester, illustrating that fatty acids of soybean oil were converted completely.  相似文献   
6.
N-甲酰吗啉的合成工艺研究进展   总被引:1,自引:0,他引:1  
简要介绍了N-甲酰吗啉的性质和应用;详细综述了N-甲酰吗啉的合成工艺方法:甲酸法、甲酸酯法、甲酰氯法、CO和超临界CO2羰基化法、吗啉烯胺氧化法,并分析了各种方法的工艺特点;指出了N-甲酰吗啉合成工艺研究的趋势。  相似文献   
7.
采用自行研制开发的Ni-Cu-Mg/Al2O3催化剂,在3 000 t/a合成反应器上进行了工业应用,并得出了吗啉生产的最佳工艺操作参数:初期操作温度206℃,床层的温升13~18℃,二甘醇操作空速0.10 h-1,循环气空速1 670~1 780 h-1,合成操作压力1.55 MPa.二甘醇基本实现全转化,合成收率≥88%,过程总收率超过84%.  相似文献   
8.
The thermal decomposition of morpholine, an additive used in the steam-water cycles of nuclear power plants, was studied using a laboratory high-pressure reactor. The measured decomposition rate constants are 2.67, 8.73 and 21.25 × 10?7 s?1 at 260, 280 and 300°C respectively. The kinetics were found to be first-order and the activation energy was 131.9 kJ/mol. Ammonia, ethanolamine, 2-(2-aminoethoxy) ethanol, methylamine, ethylamine, ethylene glycol, and acetic and glycolic acids were identified as the major breakdown products. The decomposition route proposed was validated in the field by tracking these breakdown products in water samples taken at Gentilly 2 power plant.  相似文献   
9.
对二甘醇和氨在催化剂存在及一定压力下反应制取吗啉的合成工艺路线、催化剂制备、产品分离及分析进行了详细综述.  相似文献   
10.
以吗啉和盐酸为原料合成盐酸吗啉,使其与双氰胺反应制备盐酸吗啉脒胍。重点讨论了原料配比、加料顺序、反应时间及溶剂等因素对合成工艺的影响。研究表明:吗啉:浓盐酸=1.06∶1(摩尔比),合成盐酸吗啉的收率可达98.27%,且加料顺序对反应无明显影响;以二甲苯为溶剂,盐酸吗啉:双氰胺=0.8∶1(质量比),反应时间为3.5h,盐酸吗啉脒胍的收率为97.01%。两步反应总收率可达96.97%。  相似文献   
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