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1.
徐建飞 《精细化工》2013,30(10):1198-1200
以水杨醛和溴乙酰氯为原料,经Friedel-Crafts酰基化制备得到5-溴乙酰基-2-羟基苯甲醛(Ⅱ),再与叔丁胺胺化和盐酸水解,过柱纯化后得到中间体5-{[(1,1-二甲基乙基)氨基]乙酰基}-2-羟基苯甲醛盐酸盐(Ⅲ),化合物Ⅲ再用硼氘化钠还原制得目标产物沙丁胺醇-D2(Ⅳb)。合成路线优势在于最后一步反应引入氘代同位素,保证氘代物丰度的不稀释,且操作简单,工艺流程短,副产物少,收率可达70%以上。产品经MS和1HNMR表征和确认,氘标记同位素丰度>97.1%。  相似文献   

2.
以丹皮酚(2-羟基-4-甲氧基苯乙酮)(Ⅰ)为原料,与水合肼反应得到中间体丹皮酚腙(Ⅱ),然后Ⅱ分别与各种取代苯甲醛反应合成了9个N-苄叉丹皮酚腙(Ⅲa~Ⅲi),产率为50.5%~91.9%。利用FTIR、1HNMR、13CNMR、LC-MS对目标化合物的结构进行了表征。初步探索了Ⅱ和Ⅲ的合成条件、测定了Ⅲa~Ⅲi的抗菌活性。结果表明:化合物N-(4-氟苄叉基)丹皮酚腙(Ⅲc)对金黄色葡萄球菌的最低抑菌浓度(MIC)为2 mg/L,化合物N-(2-氟苄叉基)丹皮酚腙(Ⅲb)对大肠杆菌的MIC为8 mg/L,与阳性对照药利福平抗菌效果相当。  相似文献   

3.
设计了一条水溶性多西他赛衍生物(Ⅰ)的合成路线。该路线以10-脱乙酰基巴卡丁Ⅲ(Ⅱ)为起始原料,经酯化、缩合和选择性脱保护得到关键中间体7,10-O-二苄氧酰基-多西他赛(Ⅴ),进一步与氨基酸反应,最后经钯碳催化氢解得到多西他赛衍生物(Ⅰ)。产物结构经核磁和高分辨质谱进行了表征。该合成路线操作简单,总收率64.1%,终产品纯度(HPLC)可达99%以上。  相似文献   

4.
设计了以α-萘酚为原料,在NaOH催化作用下,经与三光气(BTC)反应,合成了中间体氯甲酸萘酯,再与一甲胺-D3-盐酸盐缩合反应,制得目标产物.合成路线优势在于避免使用剧毒物光气和异氰酸酯,且操作简单,工艺流程短,副产物少,收率可达75%以上,氘标记同位素丰度不稀释.产品经HPLC、IR、MS、1 HNMR和13CNMR表征,结果表明:化学纯度>99.5%,氘标记同位素丰度>99.6%.  相似文献   

5.
以市售的左氧氟沙星羧酸为原料,以氘代甲醇为稳定同位素标记物前体,经无水哌嗪取代、双氘代甲基化、氢氧化钠水解合成出稳定同位素标记的D_3-左氧氟沙星,3步反应总收率为45.5%。目标产物经MS、~1HNMR表征确认,通过高效液相色谱确认化学纯度98%,经计算同位素丰度为97.7%。该合成路线具有操作简便、试剂廉价等优点。  相似文献   

6.
设计了以正丁醇为溶剂,氰基乙醛缩二乙醇和同位素标记尿素混合回流反应,再在酸作用下进行环化反应制备得到标题化合物。设计的合成路线操作简单、工艺流程短、副产物少,收率可达80%,同位素丰度没有降低。产物经HPLC、IR、MS、1HNMR和13CNMR表征。结果表明,化学纯度99%,同位素丰度98 atom%。  相似文献   

7.
以2-(3,4,5-三甲氧基苯基)乙酸为起始原料,经过脱甲基、酰胺化、甲基化、比希勒-纳皮拉尔斯基(Bischler-Napier-alski)环化反应、还原、脱保护基等关键反应步骤,得到稳定同位素氘标记的盐酸曲托喹酚.该合成方法原料廉价易得、简单成熟,目标产物氘同位素丰度较高.该产物经核磁共振氢谱(1 HNMR)和高...  相似文献   

8.
以氘代二乙胺与二硫化碳为原料,四溴化碳诱导催化一步合成全氘代双硫伦,最终目标产物经质谱、核磁等表征确定,总收率为88.6%,化学纯度为99.2%,同位素丰度大于98%。该合成路线简单,原料易得,反应条件易于控制,满足其作为内标物在药理学、药代动力学等方面的应用。  相似文献   

9.
徐建飞  杜晓宁  王伟  张彰 《化学世界》2012,53(10):624-628
以氨基脲盐酸盐-(2-13C,15 N3)为原料,经与苯甲醛缩合,在乙醇钠催化作用下,与氯乙酸乙酯缩合环化制得1-苯亚甲基氨基乙内酰脲,最后盐酸水解,制得1-氨基乙内酰脲盐酸盐-(2-13 C,15 N3)。合成路线优势在于反应条件温和,产物总收率高于65%。产品经IR、HPLC、NMR和MS表征结果表明:化学纯度>98.4%,13C同位素丰度>98%,15 N同位素丰度>99%。  相似文献   

10.
研究了黑色可逆热致变色染料2′-(2-氯苯氨基)-6′-二丁氨基荧烷(Ⅰ)的合成及表征。以邻氯苯胺、对苯二酚为原料,合成2-氯-4-羟基二苯胺(Ⅱ)。以间硝基苯酚为原料,经酚羟基保护、硝基还原、氨基烷基化反应、脱保护、与邻苯二甲酸酐反应合成N,N-二正丁基-4-氨基-2-羟基-2′-甲酸二苯甲酮(Ⅲ)。化合物Ⅱ与化合物Ⅲ反应合成目标产物Ⅰ,总收率56.2%,纯度99.54%(HPLC),其结构经~1HNMR、~(13)CNMR证实。  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   

13.
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   

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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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