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1.
变色酸双偶氮衍生物是一类重要的显色剂,常用于稀土、碱土和铀钍的测定。自偶氮胂M和偶氮硝羧合成以后,不对称变色酸双偶氮衍生物的研究与应用发展很快。1974年,我们合成了甲酰基、乙酰基、丙酰基偶氮羧等不对称变色酸双偶氮衍生物。实验证明,甲酰基、乙酰基和丙酰基是有效的功能团。本文介绍将甲酰基引进偶氮氯膦类试剂以后所得到的间(对)甲酰基偶氮氯膦Ⅰ对甲酰基偶氮氯膦 2-(4-氯-2-膦酸基苯偶氮)-7-(4-甲酰基苯偶氮)-1,8-二羟基萘-3,6-二磺酸Ⅱ间甲酰基偶氮氯膦 2-(4-氯-2-膦酸基苯偶氮)-7-(3-甲酰基苯偶氮)-1,8-二羟基-3,6-二磺酸  相似文献   

2.
以7-氨基头孢烷酸(7-ACA)为原料,经水解、氨基和羧基保护,制得3-羟甲基-7β-苯乙酰胺-3-头孢-4-羧酸二苯甲酯(Ⅰ),产率48%;并在乙腈中用2-碘酰基苯甲酸实现羟基选择性氧化,产物3-甲酰基-7β-苯乙酰胺-3-头孢-4-羧酸二苯甲酯(Ⅱ),收率达94%。  相似文献   

3.
应用密度泛函理论(DFT)在B3LYP/6-31G(d,p)水平下对四乙酰基二甲酰基六氮杂异伍兹烷(TADFIW)甲酰基的水解反应机理进行了研究.结果表明,TADFIW上的甲酰基水解时,甲酰基被质子化,碳氧双键中的氧原子带有负电荷0.619 e,碳原子带有正电荷0.471 e,亲核试剂水分子进攻质子化甲酰基的碳原子,同...  相似文献   

4.
糖精通过烃化和氨解生成带保护基的多甘胺。用4,5-苯并-3,6-二氧杂-l,8-辛二醇二对甲苯磺酸酯第二次烃化,得到带保护基的苯并氮杂冠醚,再用20%HCl水解生成苯并二氮杂冠醚。2,3-苯并-7,16-二氮杂-18-冠-6的总收率为12%左右。  相似文献   

5.
糖精法合成苯并氮杂冠醚   总被引:2,自引:0,他引:2  
蒋立建  王德 《化学试剂》1995,17(2):74-76
糖精通过烃化和氨解生成带保护基的多甘胺。用4,5-苯并-3,6-二氧杂-1,8-辛二醇二对甲苯磺酸酯第二次烃化,得到带保护基的苯并氮杂冠醚,再用20%HCl水解生成苯并二氮杂冠醚。2,3-苯并-7,16-二氮杂-18-冠-6的总收率为12%左右。  相似文献   

6.
报道了9-[(4氟-)-3羟-基甲基丁基]鸟嘌呤(FHBG,Ⅱ)的改进合成方法,对起始原料喷昔洛韦(Ⅲ)的氨基和一个羟基用4-甲氧基氯化三苯甲烷保护,对另一个羟基磺酯化,得到N2-(p-甲氧基苯酰基二苯基甲基)-9-[(4甲-苯磺酰)-3-p-甲氧基苯酰基二苯基-甲氧基甲基丁基]鸟嘌呤(Ⅴ),收率为70.5%;再用四丁基氟化铵(TBAF)对化合物Ⅴ亲核取代4-甲苯磺酰基团,水解脱去保护基,即得FHBG。产品经1HNMR、IR、MS表征,并用HPLC分析了Ⅴ和Ⅱ,保留时间分别为5.89 m in和4.41 m in,积分计算质量分数分别为w(Ⅴ)=99.5%和w(Ⅱ)=99.3%。  相似文献   

7.
王洋  芦晓然  骆颖哲  庞纯  彭晓宏 《精细化工》2011,28(10):941-944
以1,4-二溴-2-丁烯、4-氟苯磺酰胺、2,4,6-三异丙基磺酰胺为主要原料,采用5步法合成一种含氮的十五元三烯大环化合物———(E,E,E)-1,6-二[(2,4,6-三异丙基苯基)磺酰基]-11-[(4-氟苯基)磺酰基]-1,6,11-三氮环十五烷-3,8,13-三烯。进而使用十五元三烯大环化合物改性2.0代的聚丙烯亚胺树状聚合物(2.0G PPI,实验室自制)的外围基团,制备聚丙烯亚胺杂化树型聚合物。利用核磁共振波谱和红外光谱表征了中间产物和目标产物的结构,结果表明,所得中间产物和目标产物均符合分子设计要求,合成路线合理可行。  相似文献   

8.
制备六硝基六氮杂异伍兹烷的硝解工艺近期进展   总被引:3,自引:0,他引:3  
六硝基六氮杂异伍兹烷(HN研)是当今已工业化生产的能量水平最高的炸药,HNIW的制备包括基本母体的合成、母体的氢解、氢解产物(硝解底物)的硝解(即生成HN研)及HNIW的转晶4步。综述了近几年来制备HNIW的硝解工艺的进展(包括作者的若干研究成果),详细报道了硝解3种底物([四乙酰基二苄基六氮杂异伍兹烷(TADBIW)、四乙酰基二甲酰基六氮杂杂异伍兹烷(TADFIW)及四乙酰基六氮杂异伍兹烷(TAIW])以制备HNIW的工艺条件,并评价了各自的优、缺点。  相似文献   

9.
以1,4-二溴-2-丁烯,4-氟苯磺酰胺,2,4,6-三异丙基磺酰胺为主要原料,采用五步法合成一种含氮的十五元三烯大环化合物-(E,E,E)-1,6-二[(2,4,6-三异丙基苯基)磺酰基]-11-[(4-氟苯基)磺酰基]-1,6,11-三氮环十五烷-3,8,13-三烯。进而使用十五元三烯大环化合物改性2.0代的聚丙烯亚胺树状聚合物(2.0G PPI,实验室自制)的表面基团,制备聚丙烯亚胺杂化树形聚合物。利用核磁共振和红外光谱表征了中间产物和目标产物的结构,结果表明:所得的中间产物和目标产物均符合分子设计要求,合成路线合理可行。  相似文献   

10.
以3-甲硫基丙醇(2)与对甲基苯磺酰氯(3)发生取代反应、氧化反应得3-(甲基磺酰基)丙基-4-甲基苯磺酸(5),再以间苯二酚(6)与4-氯乙酰乙酸乙酯(7)缩合成环、水解、成酯、氢化还原得6-羟基-苯并呋喃-3-乙酸甲酯(11),以4-溴-3,5-二甲基苯酚(12)与3-甲酰基苯硼酸(13)发生suzuki偶联得4'-羟基-2',6'-二甲基-[1,1'-联苯]-3-甲醛(14),再与(4)亲核取代、还原得3-(甲基磺酰基)丙基-4-甲基苯磺酸(16),(16)与(11)缩合,最终水解得到6-({2',6'-二甲基-4'-[3-(甲磺酰基)丙酰基]-联苯}甲氧基)-2,3-二氢苯并呋喃-3-乙酸(18)。  相似文献   

11.
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   

12.
It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.  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   

18.
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   

19.
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   

20.
Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.  相似文献   

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