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放射性^99mTc标记的NMDA受体配基N2S2-Memantine的合成 总被引:9,自引:1,他引:8
以美金刚胺为原料,先与氯乙酰氯反应,再与二硫二氮缩合,最后与醋酸汞硫化氢反应脱巯基保护基得到标记前体N-[2-(N-(2-巯基乙基))氨基甲酰甲基J-N-(2-巯基乙基)-3,5-二甲基金刚烷胺基乙酰胺.关键化合物N-[2-((2-(S-(4-甲氧基苄基)巯基)乙基)氨基)乙酰基]-S-(4-甲氧基苄基)-2-氨基乙硫醇和N-[2-(S-(4-甲氧基苄基)硫基)乙基]-N-[N-(2-(S-(4-甲氧基苄基)硫基)乙基)氨基)甲酰甲基]-3,5-二甲基金刚烷胺基乙酰胺得到核磁和质谱表征,总收率为32%. 相似文献
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介绍了经改进的奥美拉唑中间体2-巯基-5-甲氧基-1 H-苯并咪唑的合成工艺。以对甲氧基苯胺为原料,经胺基保护、硝化、水解得到4-甲氧基-2-硝基苯胺,再经Pd/C催化下还原后,直接与CS2缩合成环反应制得奥美拉唑重要中间体2-巯基-5-甲氧基-1 H-苯并咪唑。对实验过程中的硝化反应和催化还原反应的条件进行了探讨。该方法具有反应条件温和、操作简便、环境污染小的特点,适合工业化生产。 相似文献
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2,3-二甲氧基-5-甲基-6-(3-甲基-2-烯-1-丁基)-1,4-苯酚的合成及其副产物的研究 总被引:1,自引:0,他引:1
2,3-二甲氧基-5-甲基-1,4-苯酚与2-甲基丁烯醇在BF3OEt2的催化下进行傅-克烷基化反应合成2,3-二甲氧基-5-甲基-6-(3-甲基-2-烯-1-丁基)-1,4-苯酚。对鲜见文献报道的副产物2,2,5-三甲基-3-氢-6-羟基-7,8-二甲氧基-苯并吡喃进行了结构鉴定并推测了其形成机理,在原料辅酶Q0、甲基丁烯醇和BR的配比为1:1.5:0.19(摩尔比),反应温度45℃,滴加时间30min,反应时间2h的条件下收率达90.24%。 相似文献
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以3,4,5-三甲氧基甲苯(Ⅰ)为原料,经过Vilsmeier-Haack反应合成了6-甲基-2,3,4-三甲氧基苯甲醛(Ⅱ),收率94.1,Ⅱ经过Dakin反应得到2,3,4-三甲氧基-6-甲基苯酚(Ⅲ),收率96.2,用溴化苄对Ⅲ进行酚羟基保护得到2,3,4-三甲氧基-6-甲基苯基苄基醚(Ⅳ),收率95.0,Ⅳ在有机碱作用下发生溴代反应,得到6-甲基-5-溴-2,3,4-三甲氧基苯基苄基醚(Ⅴ),收率92.2,Ⅴ在超声波作用下制成格氏试剂(Ⅵ),再与4-溴-2-甲基-1-苯磺酰基-2-丁烯发生格氏偶联反应得到辅酶Q10的关键中间体3-(4-苯磺酰基-3-甲基-2-丁烯基)-4,5,6-三甲氧基-2-甲基苯基苄基醚(Ⅶ),收率72.0,五步反应总收率为57.1,产物经FTIR和1H NMR确定结构。 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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《分离科学与技术》2012,47(17):2630-2641
Optical resolution of racemic mixtures of arginine and alanine was performed by chiral selective nanofiltration membrane. The chiral selective layer of the membrane was prepared by interfacial polymerization of metaphenylenediamine, trimesoyl chloride, and S (-)-2-acetoxypropionyl chloride (S-2-actoxpcl) in situ on the top of polysulfone ultrafiltration membrane. S-2-actoxpcl consists of a chiral carbon atom that has an induced chiral environment in the membrane. The membranes were characterized by FTIR, scanning electron microscopy, and atomic force microscopy to establish a structure-performance relationship. The optical resolution was performed on the membrane testing module and the effect of process parameters was determined. The results indicated that the incorporation of S-2-actoxpcl made membrane chiral selective hence membranes performed optical resolution. The resolution capacity increased by increasing S-2-actoxpcl in polymerizing solution up to 0.03% but any increase beyond 0.03% reduces the resolution capacity. More than 92% enantiomeric excess of D enantiomer was observed in the permeate of the membrane which was prepared from 0.07% trimesoyl chloride and 0.03% S-2-actoxpcl. The membrane prepared without the chain terminator exhibited less volumetric flux but more solute rejection compared to those prepared with the chain terminator. The flux of the membrane increases as the amount of the chain terminator in the reaction increases. 相似文献
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Chemoenzymatic Synthesis of 13C-Labeled S-(-)-Malic Acid The first regio- and stereospecific synthesis of S-(-)-13C-malic acid 5 with a high incorporation of 13C and excellent enantiomeric excess is described. S-(-)-13C-malic acid 5 was synthesized in a three-step reaction starting with ethyl acetate 2 and diethyl oxalate 1 . The produced sodium diethyl oxaloacetate 3 was then enantioselectively reduced with bakers' yeast to S-(-)-13C-malic acid diethylester 4 which was hydrolyzed to S-(-)-13C-malic acid 5 . 相似文献
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用锑砷烟灰制取焦锑酸钠和砷酸钠 总被引:2,自引:0,他引:2
介绍了以Na2S-NaOH作浸出剂,在强碱性介质中浸出锑砷烟灰中锑和砷,然后继续保持碱性条件,用氧化剂氧化浸出液,使锑、砷分离,分别制取焦锑酸钠NaSb(OH)6和砷酸钠Na3AsO4;而烟灰中的其它金属离子富集于浸出渣中得以回收。 相似文献
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海洋微生物溶菌酶的发酵优化与中试生产 总被引:3,自引:0,他引:3
以海洋细菌S-12-86为试验菌株,采用摇瓶发酵优化的方式,研究培养基组分(碳源、氮源、碳源与氮源的比例、金属离子)与发酵条件(培养温度、接种体积分数、装液体积分数、起始pH值、产酶周期)对海洋微生物溶菌酶产量的影响,并进行中试放大试验。结果表明:该菌产酶最佳培养基组分为:葡萄糖10 g/L,蛋白胨5 g/L,MgSO45 g/L,CaCl22 g/L;最适发酵培养温度为30℃,接种体积分数为4.0%,装液体积分数为10.0%,起始pH值为8.0,发酵周期24 h。海洋细菌S-12-86发酵优化后的产酶量(25636.8 U/mL)较优化前的产酶量(14454.4 U/mL)提高了75.4%。海洋微生物溶菌酶中试发酵的产酶量达26697.87 U/mL。说明摇瓶发酵优化条件可以应用于海洋微生物溶菌酶中试生产上。 相似文献
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Purification and Characterization of Three Alkaline Endopolygalacturonases from a Newly Isolated Bacillus gibsonii 总被引:1,自引:0,他引:1
A newly isolated Bacillus gibsonii, designated as S-2 (CGMCC1215), was cultivated for production of alkaline pectinases utilizing sugar beet pulp as growth substrate. Purification of three alkaline endopolygalacturonases (endoPGs) from the crude pectinases extract was carried out by ultra-filtration, ammonium sulphate fractionation and ion-exchange chromatography, and their enzyme activities characterized. The three purified alkaline endoPGs, designated as S-I, S-II, and S-III, had a molecular weight about 38 kDa as determined by SDS-PAGE. The Km value and optimal temperature for optimal enzyme activities of S-I, S-II and S-III were 1.2 mg/mL and 60℃, 0.9 mg/mL and 55℃, 1.1 mg/mL and 60℃, respectively. Their best performances were given at an optimal pH 10.5, and sodium polygalacturonate was found to be the best substrate. The isoelectric points of S-I, S-II and S-III were 5.4, 7.4, and 8.2, respectively. Surfactants of Tween-80 and Tween-20 and metal ions such as Mg2+ and Ca2+ stimulated the activity of S-I, S-II and S-III, whereas S-III was inhibited by Ca2+, and Mn2+ and Zn2+ ions inhibited the activity of the three enzymes. 相似文献
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考察了改性木质素磺酸钠GCL3S系列产品对墙地砖陶瓷浆料应用性能的影响,结果表明,GCL3S具有较好的分散稳定性能。当低相对分子质量(以下简称分子量)的GCL3S-1掺量(分散剂占陶瓷粉料的质量分数,下同)为0.3%时,固含量(固体占陶瓷浆体的质量分数,下同)为71.26%的陶瓷浆料流出时间仅为41.79 s,厚化度为1.37;随GCL3S分子量增加,陶瓷浆料性能先提高后降低,重均分子量Mw=27 700的GCL3S-2对浆料的流动性及分散稳定性能最好。GCL3S产品与水玻璃、六偏磷酸钠、焦磷酸钠、三聚磷酸钠复配能进一步提高其应用性能,其中与六偏磷酸钠按质量比1∶1复配,总掺量为0.2%时,陶瓷浆料流出时间仅38.81 s,分散性能明显优于目前常用的无机盐分散剂。 相似文献