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1.
苯并咪唑类化合物在医药、农药等方面具有广泛的应用,因此这类化合物合成的新方法备受关注.从合成苯并咪唑类化合物的不同的原料出发,综述了近年来催化合成苯并咪唑化合物的研究新进展.  相似文献   

2.
苯并咪唑类化合物在药物化学、生物化学、配位化学以及催化、分子识别、阻燃等领域具有重要应用.氨基酸类化合物是一类来源广泛的功能性合成子,因此近年来基于氨基酸的苯并咪唑合成与功能改性研究受到人们的广泛关注.综述了以各种天然与非天然氨基酸为原料,以溶液法、微波法、固相法等合成技术合成与改性苯并咪唑的新进展.  相似文献   

3.
苯并咪唑类化合物广泛应用于医药、农药等领域,也在阻燃剂中具有重要应用.因此,利用微波辅助方法快速、高效地合成苯并咪唑类化合物已成为近年来的研究热点,本文对此进行了综述,并从经济与规模化制备苯并咪唑等方面进行了展望.  相似文献   

4.
报道了在水相中可见光下1,2-苯二胺与苯腈的环化反应,合成了一系列苯并咪唑类化合物.反应用便宜、易处理、对环境无污染的曙红Y作为光催化剂.室温下在水相中反应,获得的产物有较好收率,最高产率可达到91%.提供了一种合成苯并咪唑类化合物的简便经济的方法.  相似文献   

5.
苯并咪唑稠合二氢苯并唑是一类复杂的氮氧杂环,在生物医药和功能性材料中具有较高的应用价值.本文在空气氛围中以苯并咪唑和2-溴苯酚为原料、廉价Cu(Ⅱ)为催化剂,采用"一锅法"合成了苯并咪唑稠合二氢苯并唑类化合物,反应经历了N-芳基化、sp~2 C-H活化、C-O环化的串联过程.研究表明,该反应对于苯并咪唑类衍生物,以及其他反应底物(如2-碘苯酚和2-羟基苯硼酸)均具有一定的官能团耐受性.本文为高效合成苯并咪唑稠合二氢苯并唑类化合物提供了一种简便方法.  相似文献   

6.
成功开发了由铁粉促进"一锅法"合成1-苯基苯并咪唑类化合物的简易合成方法.以取代邻硝基二苯胺为原料,液体有机酸为溶剂,在铁粉作用下还原并直接环合生成1-苯基-苯并咪唑类化合物,产率80%~93%.通过高效液相色谱(HPLC)监测分析反应进程,探讨反应的机理,并确定了最佳反应条件.该合成方法条件温和,操作简单,原料易得,产率较高,为该类化合物的合成提供了一种新的便利方法.  相似文献   

7.
苯并咪唑类化合物作为一种重要的N-杂有机化合物,在药物化学、材料化学、合成化学等领域显示出广阔的应用前景。传统方法合成苯并咪唑具有速度缓慢、效率低下等缺点。微波辅助合成苯并咪唑由于速度快、反应时间短、收率高、易纯化以及环境友好等优点越来越受到人们的关注。本文介绍了近年来微波辅助合成苯并咪唑的研究与应用。  相似文献   

8.
合成了一系列取代甲基硫代苯并咪唑类化合物,并在过氧乙酸的氧化下得到了 取代甲基亚磺酰基苯并咪唑类化合物,收率较好(79%~97%),代替了用间氯过氧苯 甲酸进行氧化,反应过程稳定,降低了成本。  相似文献   

9.
苯并咪唑类化合物在多种有机溶剂和水溶液中能够发出特征荧光,而且在一定条件下荧光性质会因多种因素而发生改变,因此其在荧光检测领域的应用受到了广泛的关注.综述了苯并咪唑类传感器的合成及其在各种金属离子、阴离子、无机物小分子、金属氧化物纳米粒子和有机小分子等物质检测中应用的新进展,并展望了苯并咪唑基荧光化学传感器的发展趋势.  相似文献   

10.
李湘广  杨秉勤  谷利军  宁伟 《应用化学》2009,26(10):1184-1188
将二茂铁磺酰氯或二茂铁甲酰氯和1H-苯并咪唑衍生物反应,合成了12个未见文献报道的N-(酰基二茂铁)苯并咪唑类化合物,用IR、1HNMR、元素分析和MS对其结构进行了表征。结果表明,含有活泼氢的苯并咪唑衍生物能与二茂铁酰氯生成相应的N-(酰基二茂铁)苯并咪唑衍生物,并有较好的收率。  相似文献   

11.
采用AA-6800型石墨炉原子吸收光谱仪研究了土壤-巴戟天系统中铅的分布情况,包括不同地段、不同土壤类型、不同土壤pH值对土壤-巴戟天入药部位根和果实中铅的含量影响。实验结果表明,环境条件变化对土壤-巴戟天系统铅含量有一定的影响,其中土壤的pH值对土壤中的有效铅浓度及巴戟天的铅含量影响较大。  相似文献   

12.
溪黄草根茎叶微量元素含量的测定   总被引:3,自引:0,他引:3  
用等离子体原子发射光谱法对溪黄草根、茎、叶等不同部位微量元素的含量进行了测定,溪黄草不同部位都含有18种微量元素,其不同部位微量元素分布有共同之处,也存在明显的差别。  相似文献   

13.
The process dependence of pressure-specific volume-temperature (pvT) measurement for an amorphous polymer, acrylonitrile-butadiene-styrene (ABS), was investigated. The influences of different measurement processes (heating, cooling, compression, and decompression with different rates) were considered in the pvT measurements. The pvT measurements of isobaric cooling and heating with different cooling and heating rates (2, 5, and 10 °C/min) and isothermal compression and decompression with different compression and decompression rates (up to 920 bar/s) were conducted. The testing temperature ranged between 40 and 230 °C and the pressure ranged between 20 and 2200 bar. The obtained results demonstrated that the pvT diagram will be significantly different depending on the direction in which the pressure or temperature is changing and also on the rate of the change. Isobaric pvT diagrams are different between cooling and heating. Fast cooling accelerates phase transitions, while fast heating reverses. Specific volume at the same pressure and temperature in decompression process is lower than that in compression. Compression and decompression leads to different pvT curves. Compression and decompression rates have different effects on specific volume in different states.  相似文献   

14.
NIR spectroscopy has been applied to the study water in the interlayer of the autunite minerals. The spectra of autunites and metaautunites in the first HOH fundamental overtone are different and the spectra of autunites of different origins in the 6000-7500 cm(-1) region are considerably different. A number of conclusions are made based upon the NIR spectra: (a) The spectra of different autunites are different in the NIR spectral region; (b) the spectra of metaautunites show similarity; (c) the spectra of metaautunites are different from that of autunites. NIR spectroscopy provides a method of determination of the structure of water in the interlayer of natural autunites. The implication from the variation in the NIR spectra is that the structural arrangement of water for different autunites is different and is sample dependent. NIR spectroscopy has a wide potential for the study of the autunite minerals.  相似文献   

15.
The stratigraphies of decorated walls in ancient Herculaneum, Italy, were analyzed by single-sided 1H NMR. A large version of the NMR-MOUSE® with a maximum penetration depth of 25 mm was used to map proton density profiles at different positions of the Mosaic of Neptune and Amphitrite showing considerable differences between different tesserae and the mortar bed at different times of the year. In the House of the Black Room, different mortar layers were observed on painted walls as well as different proton content in different areas due to different moisture levels and different conservation treatments. The proton density profiles of the differently treated areas indicated that one method leads to higher moisture content than the other. Untreated wall paintings from different times were profiled in a recently excavated room at the Villa of the Papyri showing two different types of mortar layer structures which identify two different techniques of preparing the walls for painting. Reflectance Fourier mid-infrared spectroscopy and in situ X-ray fluorescence measurements complemented the NMR measurements and provided additional insight into the identification of organic coatings as well as the nature of the pigments used, respectively. The information acquired nondestructively by NMR is valued for elaborating conservation strategies and for identifying different schools of craftsmen who prepared the mortar supports of the wall paintings.  相似文献   

16.
Richarz AN  Wolf C  Brätter P 《The Analyst》2003,128(6):640-645
In the human body, there exists over 200 different cell types, which differ in size and structure and have specialised functions in the organism. Therefore it can be assumed that these different cells also contain different proteins necessary to carry out the respective specialised functions. This supposed different metalloprotein composition in different human organs cannot be demonstrated by determination of total element concentrations. Therefore investigations of the different protein-bound forms of the elements were achieved by speciation analysis: The biomolecules were separated by size exclusion chromatography and the elements detected on-line in the eluate by a hyphenated inductively coupled plasma mass spectrometer (ICP-MS). For the interpretation of the obtained element profiles, an identification of the signals and their assignment to different metalloproteins was necessary. This identification was carried out by means of specific protein assays, i.e. enzymatic assays or immunochemical reactions, in collected fractions of the chromatographic separations. A comparison of the element binding pattern in cytosols of different human organs was then possible. The optimised method was applied to tissue cytosols of different human organs. As expected, the element patterns varied for different organs of the same patient and for the same organ of patients with different diseases. Metalloproteins and their bound metals could consequently be considered as biological markers for physiological differences or pathological changes in human tissues.  相似文献   

17.
宁夏枸杞甜菜碱提取物高效液相色谱指纹图谱研究   总被引:1,自引:0,他引:1  
建立宁夏枸杞甜菜碱提取物高效液相色谱指纹图谱,为鉴别不同来源的宁夏枸杞提供依据。以10批宁夏不同产地的宁夏枸杞主栽品种"宁杞Ⅰ号"样品建立枸杞甜菜碱提取物指纹图谱共有模式,采用"中药色谱指纹图谱相似度评价系统"软件进行数据处理,对15批不同来源的枸杞样品进行了分析。结果表明:8个特征峰构成了宁夏枸杞甜菜碱提取物的色谱指纹图谱,不同产地、不同品种的枸杞样品甜菜碱提取物指纹图谱存在差异;建立的枸杞甜菜碱提取物高效液相色谱(HPLC)指纹图谱对不同产地、不同品种枸杞的鉴别有参考价值。  相似文献   

18.
The chemical components and medicinal properties of different medicinal parts of Angelica sinensis are often used as medicine after being divided into the head, body and tail of Angelica sinensis. In this study, the chemical components of different medicinal parts in different periods were analyzed by GC-MS for the first time, and the differences of the accumulation rules of chemical components in different medicinal parts of Angelica sinensis were obtained. This study demonstrated that the differences of composition accumulation in different medicinal parts of Angelica sinensis were mainly reflected in the types and relative contents of compounds. The study found that the number of compounds in different medicinal parts of Angelica sinensis in each period were different and the change rules of the same compound in different medicinal parts were also different. The number of compounds in the tail of Angelica sinensis was the least in April, and the largest in October. The content of ligustilide in the body of Angelica sinensis was higher in April and was the highest in the tail in October. The relative content of butylidenephthalide in the head was the highest in October. The relative contents of senkyunolide A and butylphthalide in the head were decreased in October, while the contents in the body and tail increased, indicating that the compounds that accumulate in the head may transfer to the body and tail in later stages of growth. This study clarified the differences in the accumulation of chemical components in different medicinal parts of Angelica sinensis, which could provide a theoretical basis for the reasons for the differences of chemical components in the different medicinal parts.  相似文献   

19.
宋小平  韩长日 《有机化学》1998,18(4):377-381
建立了不同分子环境中甲基中心碳原子电负性的计算模型, 计算了一些常见的CH~3-Z分子模型中甲基中心碳原子的电负性。结果表明:不同分子环境中的甲基具有不同的诱导效应参数, 该参数表现出规律性, 并可用于结构-性能的相关分析。  相似文献   

20.
一种提高色谱指纹谱保留时间重现性的新方法   总被引:4,自引:0,他引:4  
王龙星  肖红斌  梁鑫淼 《分析化学》2003,31(10):1232-1236
通过色谱热力学分析发现,在相同的分析条件下,即使采用不同的液相色谱系统或不同的色谱柱,组分的保留时间存在简单的线性关系,应用该线性关系可提高不同反相C18柱间保留时间重现性,经过实际样品在不同操作条件下的验证,表明该方法是正确而可行的。  相似文献   

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