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1.
以巴卡亭Ⅲ(Ⅰ)为原料,经酯化、缩合、选择性脱保护等反应得到2'-O-[4-N,N-二甲基氨基-2(R)-氟代丁酰基]-紫杉醇盐酸盐(Ⅵ)。中间体7-O-苄氧甲酰基-紫杉醇(Ⅳ)与(R)-4-N,N-二甲基氨基-2-氟代丁酰氯盐酸盐(Ⅶ)酯化得到2'-O-[4-N,N-二甲基氨基-2(R)-氟代丁酰基]-7-O-苄氧甲酰基-紫杉醇盐酸盐(Ⅴ),Ⅴ经氢解脱保护得到Ⅵ。探讨了三氟乙酸和乙酸体积比对合成化合物Ⅳ反应时间的影响;考察了在制备化合物Ⅴ时,(R)-4-N,N-二甲基氨基-2-氟代丁酸盐酸盐(Ⅷ)和催化剂4-二甲氨基吡啶(4-DMAP)的用量对Ⅳ转化率的影响。得到优化的实验条件为:V(三氟乙酸)∶V(乙酸)=1∶8;n(Ⅳ)∶n(4-DMAP)∶n(Ⅷ)=1∶3∶3。得到的产物Ⅵ采用核磁、质谱和碳谱进行了表征。该合成工艺操作简易,总收率大于60%,并且目标产物Ⅵ的HPLC纯度可达99%。  相似文献   

2.
以2-氯-4-氟苯甲酸为起始原料,经硫酸和硝酸硝化,氯化亚砜酰化后与N-甲基-N-异丙基磺酰胺反应得到化合物N-(2-氯-4-氟-5-硝基苯甲酰)-N′-异丙基-N′-甲基磺酰胺;制得N-(2-氯-4-氟-5-硝基苯甲酰)-N′-异丙基-N′-甲基磺酰胺经钯碳加氢硝基还原,然后与氯甲酸乙酯反应得到化合物N-[2-氯-4-氟-5-{(乙氧基羰基)氨基}苯甲酰]-N′-异丙基-N′-甲基磺酰胺;N-[2-氯-4-氟-5-{(乙氧基羰基)氨基}苯甲酰]-N′-异丙基-N′-甲基磺酰胺与3-甲基氨基-4,4,4-三氟丁烯酸乙酯进行环化,得到目的产物苯嘧磺草胺。总收率68.0%(以2-氯-4-氟苯甲酸计)。经核磁谱图分析,所得化合物与目的产物苯嘧磺草胺结构一致。  相似文献   

3.
以N-叔丁氧羰基-1,4-丁二胺和N-(4-溴丁基)邻苯二甲酰亚胺为原料,经取代及保护两步反应合成N1-(4-邻苯二甲酰亚胺)丁基-N1,N4-二叔丁氧羰基-1,4-丁二胺(Ⅳ),然后肼解得N1-氨基丁基-N1,N4-二叔丁氧羰基-1,4-丁二胺(Ⅴ),3步反应总收率38%;Ⅴ与9-蒽甲醛缩合后用NaBH4还原,产物提纯后脱保护得目标产物N1-(4-氨基丁基)-N4-(9-蒽甲基)-1,4-丁二胺盐酸盐(Ⅶ),3步反应总收率约7 5%。化合物Ⅳ~Ⅶ的结构经13CNMR,1HNMR和ESI-MS确证,并对反应条件进行了初步优化。  相似文献   

4.
(S)-2-[(苄氧羰基)氨基]-3-羟基丙酸苄酯(Ⅰ)经亚磷酸二苯酯处理得到了(S)-2-[(苄氧羰基)氨基]-2-(苄氧羰基)乙基膦酸酯(Ⅱ);化合物Ⅱ经新戊酰氯介导活化后,与(S)-(+)-2,2-二甲基-1,3-二氧戊环-4-甲醇(Ⅲ)缩合,并由碘氧化得到新化合物(R)-2,3-异亚丙基-sn-甘油基{(S)-2-[(苄氧羰基)氨基]-2-(苄氧羰基)-1-氧乙基}膦酸酯(Ⅳ);然后,化合物Ⅳ在三氟乙酸的作用下脱除异丙叉基得到(R)-2,3-二羟基丙基-sn-甘油基{(S)-2-[(苄氧羰基)氨基]-2-(苄氧羰基)-1-氧乙基}膦酸酯(Ⅴ);在1-乙基-(3-二甲氨基丙基)碳酰二亚胺盐酸盐(EDCI)的作用下,中间体Ⅴ与硬脂酸进一步乙酰化,以85.8%的产率得到了(R)-2,3-双(硬脂酰基)丙酰基{(S)-2-[(苄氧羰基)氨基]-2-(苄氧羰基)-1-氧乙基}膦酸酯(Ⅵ);中间体Ⅵ经氢解得到了1,2-二硬脂酰基-sn-甘油-3-磷脂酰丝氨酸(Ⅶ)。对主要合成步骤的反应条件进行了优化,并进行了验证和放大实验。产物Ⅶ共经历5步反应,总产率为57.1%。采用FTIR、HRMS和...  相似文献   

5.
以对胍基苯甲酸盐酸盐和对羟基苯乙酸-N,N-二甲基甲酰氨基甲酰甲酯为原料、草酰氯为卤化剂、吡啶为缚酸剂合成了甲磺酸卡莫司他关键中间体N,N-二甲基氨基甲酰甲基-4-(4-胍基苯甲酰氧基)苯乙酸酯盐酸盐,总收率96.6%,并优化了其合成工艺。产物结构经1 HNMR、13 CNMR和质谱确证。该合成方法原料易得,反应条件温和,适合工业化生产。  相似文献   

6.
以邻甲基苯乙酮为原料,依次经相转移催化下的高锰酸钾碱性氧化、甲醇酯化、甲氧胺盐酸盐肟化和N-溴代丁二酰亚胺(NBS)溴化后,得到制备肟菌酯的关键中间体——(E)-2-(2'-溴甲基苯基)-2-羰基乙酸甲酯-O-甲基酮肟。产品结构经熔点和1H-NMR表征。通过优化反应条件,总收率可达52%。  相似文献   

7.
本文研究了使用带水剂分水促进N-烷基化反应合成N,N-二甲氧基羰基甲基取代苯胺类染料中间体的新工艺。以间氨基乙酰苯胺(或2-氨基-4-乙酰氨基苯甲醚,统称取代苯胺)和氯乙酸甲酯为原料,碳酸钠为缚酸剂,溴化钠为催化剂,采用带水剂合成3-乙酰氨基-N,N-二甲氧基羰基甲基苯胺(或2-甲氧基-5-乙酰氨基-N,N-二甲氧基羰基甲基苯胺)。确定其最佳工艺条件为:n(碳酸钠)∶n(取代苯胺)=1.2∶1,催化剂溴化钠量为取代苯胺(质量分数)的10%,0.5 mol取代苯胺投料,取100g甲苯作为带水剂,回收带水剂(含氯乙酸甲酯)可用于下批合成(即套用)。  相似文献   

8.
以4-氯-3-磺胺基苯甲酸和2,3-二氢-2-甲基-1H-吲哚为主要原料,经3步反应合成了降压药吲哒帕胺.4-氯-3-磺胺基苯甲酸与氯化亚砜反应得4-氯-3-磺胺基苯甲酰氯(Ⅰ),产率98.0%;2,3-二氢-2-甲基-1H-吲哚与亚硝酸反应得到N-亚硝基-2,3-二氢-2-甲基-1H-吲哚(Ⅱ),不用分离出Ⅱ,直接用钯/碳催化剂催化氢化得到N-氨基-2,3-二氢-2-甲基-1H-吲哚(Ⅲ),再进一步制成N-氨基-2,3-二氢-2-甲基-1H-吲哚盐酸盐(Ⅳ),产率92.0%;Ⅰ和Ⅳ反应得到目标产物吲哒帕胺(Ⅴ),产率92.5%,所得产品符合药典标准.  相似文献   

9.
5-甲基-2-(对-N,N-二苯氨基苯基)-4-乙酰基(口恶)唑的合成   总被引:1,自引:2,他引:1  
将亚硝酸钠溶液加入到溶于冰醋酸中的乙酰丙酮中,温度保持在0~5℃得到了羟亚氨基乙酰丙酮(I),产率44%.对-N,N-二苯氨基苯甲醛(Ⅱ)由三苯胺、N,N-二甲基甲酰胺、三氯氧磷经Vilsmeier反应合成,产率89%.羟亚氨基乙酰丙酮和对-N,N-二苯氨基苯甲醛溶于冰醋酸中,在干燥的氯化氢作用下,温度保持在0~5℃,首先生成盐酸盐中间体(Ⅲ),然后控制温度为40~50℃,盐酸盐在冰醋酸中经锌粉还原为5-甲基-2-(对-N,N-二苯氨基苯基)-4-乙酰基 唑(Ⅳ),反应时间3 h,产率22%.  相似文献   

10.
以2-氯-6-甲基苯胺为起始原料,在吡啶的催化下,以99%的转化率得到酰化产物(E)-N-(2-氯-6-甲基苯基)-3-乙氧基丙烯酰胺(Ⅲ);Ⅲ在以水为主的溶剂中与N-溴代丁二酰亚胺(NBS)、硫脲经“一锅法”连续反应得化合物2-氨基-N-(2-氯-6-甲基苯基)-5-噻唑甲酰胺(V);V经纯化后与4,6-二氯-2-甲基嘧啶反应得化合物2-(6-氯-2-甲基嘧啶-4-氨基)-N-(2-氯-6-甲基苯基)-5-噻唑甲酰胺(Ⅵ);Ⅵ与1-(2-羟乙基)哌嗪缩舍得达沙替尼(Ⅶ),总收率为71%.该合成方法条件温和、反应步骤少、收率高.  相似文献   

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Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

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Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.  相似文献   

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In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.  相似文献   

18.
Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

19.
收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

20.
收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

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