四氢小檗碱衍生物的合成与表征

文章根据文献中具有降血糖作用的四氢黄连碱型季铵化合物的构效关系,合成了一系列N-7位带有酰胺侧链的四氢小檗碱类衍生物,所得目标产物均经IR、1H NMR和ESI-MS确认。     

四氯苯酐的制备

<正> 四氯苯酐为无色、无味的针状结晶或粉末,可溶于如二氧六环类的有机溶剂,不溶于冷水,除主要用作阻燃剂外,还大量地用于聚酯、环氧树脂的合成中,同时也是农药、染料、合成药物、增塑剂合成中必不可少的重要中间体化合物。四氯苯酐主要是由邻苯二甲酸酐在溶剂中进行催化氯化反应制得,也可以通过氧化3,4,5,6-四氯邻二甲苯制得。1用发烟硫酸或硫酸酐作溶剂制四氯苯酐在高温条件下邻苯二甲酸酐的氯化反应要在催化剂催化的条件下进行,例如使用碘(或碘的化合物)     

四氧化三铁纳米颗粒的混合碱法合成

采用混合碱媒介法（CHM）制备四氧化三铁纳米颗粒,探索了制备工艺，通过SEM、XRD、TEM表征方法研究了实验合成条件对四氧化三铁纳米产物的形貌和微结构的影响。结果表明：以酞氟铁为原料用混合碱法可制得粒度均匀、粒径范围在100-200nm的四氧化三铁纳米颗粒，所制备的样品具有粒径小、粒度均匀、分散性较好的特点，是性能优良的磁性材料。     

N,N''''-双甲基-N,N''''-双(2,3,4,5,6-五羟基正己基)-2,3,5,6-四碘对苯二甲酰胺的合成

以对苯二甲酸和碘为原料,50%发烟硫酸为溶剂,制得2,3,5,6-四碘对苯二甲酸,再通过氯化亚砜进行酰氯化,最后与葡甲胺反应合成了标题化合物.其结构通过元素分析、红外光谱、核磁共振氢谱,质谱得到确证.运用正交实验优化了酰胺化反应条件三乙胺为缚酸剂,四碘对苯二甲酰氯和葡甲胺为反应物,它们的物质的量比为2.112.4,反应温度为40℃时,产率高达71.5%.     

四嗪衍生物的合成及其抗癌性能的研究

研究了合成标题化合物时各种因素对产率的影响,发现用三聚乙醛解聚制备的新鲜乙醛为原料,是至关重要的。乙醛与水合肼反应温度为5～10℃,六氢四嗪氧化脱氢时间72h,并以3%Pd/C取代PtO     

从植物十大功劳中制取四氢小檗碱的工艺研究

研究从植物十大功劳中制取四氢小檗碱 (THB)的生产工艺。用比较法来选择盐酸小檗碱的提取工艺 ,用正交试验法选择小檗碱最佳氢化条件。从十大功劳中制取四氢小檗碱的生产工艺为 :用酸水浸渍法提取盐酸小檗碱粗品 ,粗品以硼氢化钾为还原剂 ,乙醇作为溶剂 ,用水浴加热反应 ,最佳氢化工艺条件是乙醇浓度为 70 % ,乙醇用量为粗品的 7倍量 ,硼氢化钾先用水溶解逐渐加入。实验表明 :酸水浸渍法提取盐酸小檗碱得率较高且操作简单 ;A2 B2 C3为最佳氢化工艺条件     

N，N′-双甲基-N，N′-双（2，3，4，5，6．五羟基正己基）-2，3，5，6-四碘对苯二甲酰胺的合成

以对苯二甲酸和碘为原料,50%发烟硫酸为溶剂,制得2,3,5,6-四碘对苯二甲酸,再通过氯化亚砜进行酰氯化,最后与葡甲胺反应合成了标题化合物。其结构通过元素分析、红外光谱、核磁共振氢谱,质谱得到确证。运用正交实验优化了酰胺化反应条件:三乙胺为缚酸剂,四碘对苯二甲酰氯和葡甲胺为反应物,它们的物质的量比为2.1∶1∶2.4,反应温度为40℃时,产率高达71.5%。     

从植物十大功劳中制取四氢小檗碱的工艺研究

研究从植物十大功劳中制取四氢小檗碱（THB）的生产工艺。用比较法来选择盐酸小檗碱的提高工艺，用正交试验法选择小檗碱最佳氢化条件。从十大功劳中制取四氢小檗碱的生产工艺为：用酸水浸渍法提取盐酸小檗碱粗品，粗品以硼氢化钾为原还剂，乙醇作为溶剂，用水浴加热反应，最佳氢化工艺条件是乙醇浓度为70％，乙醇用量为粗品的7倍量，硼氢化钾先用水溶解逐渐加入。实验表明：酸水浸渍法提取盐酸小檗碱得率较高且操作简单；A2B2C3为最佳氢化工艺条件。     

四嗪衍生物的合成及其抗癌性能的研究Ⅱ.钯/碳催化氧化合成3,6-二甲基-1,6-二氢-1,2,4,5-四嗪

研究了合成标题化合物时各种因素对产率的影响,发现用三聚乙醛解聚制备的新鲜乙醛为原料,是至关重要的.乙醛与水合肼反应温度为5～10℃,六氢四嗪氧化脱氢时间72h,并以3%Pd/C取代PtO2作催化剂,产率40%.     

四嗪衍生物的合成及其抗癌性能的研究：Ⅱ.钯／碳催化氧化合成3,6—二甲基— ？

研究了合成标题化合物时各种因素对产率的影响，发现用三聚乙醛解聚制备的新鲜乙醛为原料，是至关重要的。乙醛与水合肼反应温度为５－１０℃，六氢四嗪氧化脱氢时间７２ｈ，并以３％Ｐｄ／Ｃ取代ＰｔＯ２作催化剂，产率４０％。     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

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.     

Insect antifeedant properties of anthranoids from the genusVismia

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.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

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.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

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.     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。