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由季铵盐合成有机胂二茂铁衍生物杜洪光,师树简(北京化工大学应用化学系,北京,100029)关键词有机胂,二茂铁衍生物,铵甲碘化物,亲核取代关于二茂铁季铵盐的亲核取代反应已有较多报道[1~4],但对于含胂二茂铁季铵盐的这类反应还未见诸文献,由碘化[2-... 相似文献
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Wanda Baer-Dubowska Maria Narona Violetta Krajka-Ku
niak 《Molecules (Basel, Switzerland)》2021,26(16)
Naturally occurring pentacyclic triterpenoid oleanolic acid (OA) serves as a good scaffold for additional modifications to achieve synthetic derivatives. Therefore, a large number of triterpenoids have been synthetically modified in order to increase their bioactivity and their protective or therapeutic effects. Moreover, attempts were performed to conjugate synthetic triterpenoids with non-steroidal anti-inflammatory drugs (NSAIDs) or other functional groups. Among hundreds of synthesized triterpenoids, still the most promising is 2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oic acid (CDDO), which reached clinical trials level of investigations. The new group of synthetic triterpenoids are OA oximes. The most active among them is 3-hydroxyiminoolean-12-en-28-oic acid morpholide, which additionally improves the anti-cancer activity of standard NSAIDs. While targeting the Nrf2 and NF-κB signaling pathways is the main mechanism of synthetic OA derivatives′ anti-inflammatory and anti-cancer activity, most of these compounds exhibit multifunctional activity, and affect cross-talk within the cellular signaling network. This short review updates the earlier data and describes the new OA derivatives and their conjugates in the context of modification of signaling pathways involved in inflammation and cell survival and subsequently in cancer development. 相似文献
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以松香基季铵盐(脱氢枞基三甲基溴化铵,标记为DTAB)为模板剂、正硅酸乙酯为硅源、氨水为碱性介质成功合成出具有纳米片状形貌的六方有序超微孔二氧化硅材料。采用X射线衍射、N2吸附-脱附、透射电镜、扫描电镜等手段对样品进行表征,结果表明,体系中模板剂添加量、硅源添加量、碱性介质添加量、晶化温度、搅拌时间对前驱体的有序度有着较大的影响。当物质的量之比为nSi O2∶nDTAB∶nNH3·H2O∶nH2O=1.0∶0.1∶11.3∶924.0,晶化温度为373 K,搅拌时间为24 h,所得样品有序度最高。经煅烧后样品具有较大的比表面积(1 024 m2·g-1)和孔容(0.56 cm3·g-1),以及狭窄的孔径分布(集中于1.80 nm)。 相似文献
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以松香基季铵盐(脱氢枞基三甲基溴化铵,标记为DTAB)为模板剂、正硅酸乙酯为硅源、氨水为碱性介质成功合成出具有纳米片状形貌的六方有序超微孔二氧化硅材料。采用X射线衍射、N2吸附-脱附、透射电镜、扫描电镜等手段对样品进行表征,结果表明,体系中模板剂添加量、硅源添加量、碱性介质添加量、晶化温度、搅拌时间对前驱体的有序度有着较大的影响。当物质的量之比为nSio2:nDTAB:nNH3·H2O:nH2O=1.0:0.1:11.3:924.0,晶化温度为373K,搅拌时间为24h,所得样品有序度最高。经煅烧后样品具有较大的比表面积(1024 m2·g-1)和孔容(0.56 cm3·g-1),以及狭窄的孔径分布(集中于1.80 nm)。 相似文献
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季铵盐型表面活性剂的合成及物化性能测定 总被引:17,自引:1,他引:16
从脂肪酸和N-(2-羟乙基)乙二胺开始,经过咪唑啉中间体,合成了12种未见文献报道的新化合物,其中3种为具有不同类型特性基团的新型两性表面活性剂、3种为新型阳离子表面活性剂,并测定了它们的物化性能。 相似文献
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合成了一系列过渡金属Zn取代的Keggin型磷钨杂多酸的季铵盐,采用傅里叶变换红外光谱(FTIR)、X射线衍射(XRD)等方法表征了杂多化合物的结构.并将其用于苯甲醇无溶剂氧化合成苯甲醛的反应,考察了催化剂种类、反应条件对苯甲醇氧化的影响.实验结果表明,在无任何溶剂的情况下,Zn取代的Keggin型磷钨四丁基铵盐具有最佳的催化活性,反应时间仅为30 min,苯甲醇的转化率可以达到95.6%,苯甲醛的选择性达到了96.4%.在对杂多酸季铵盐结构的研究基础上,对可能的反应机理进行了初步探讨. 相似文献
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季铵盐催化合成端烯丙基聚氧化烯大单体 总被引:8,自引:0,他引:8
用季铵盐作催化剂,由聚氧 化乙烯-氧化丙烯嵌段共聚物和烯丙基氯合成了端烯丙基聚氧化烯大单体,考察了催化剂及其用量,溶剂及反应温度,反应时间对反应封端率的影响,确定了最佳反应条件;与Williamson醚合成法比较,季铵盐催化法操作简便安全,并且可以制得封端率高的端烯丙基聚氧化烯大单体。 相似文献
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Joo-Young Park Jang-Joo Kim Kyung-Hoon Kim Jeong-Yeol Moon Dae-Won Park 《Reaction Kinetics and Catalysis Letters》2001,74(1):29-40
The synthesis of phenoxymethyl ethylene carbonate from carbon dioxide and phenyl glycidyl ether was investigated in a semi-batch
reactor using crosslinked polystyrene beads containing pendant quaternary ammonium salts as catalysts. The catalysts were
prepared by suspension copolymerization of styrene, divinylbenzene (DVB) and vinylbenzyl chloride (VBC), followed by quaternization
using trialkylamines. The influence of VBC and DVB concentration, the structure of trialkylamine, and the type of solvent,
on the catalytic behavior are discussed. A kinetic study was also carried out to better understand the reaction steps.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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Main observation and conclusionThe binding behaviors of three structurally similar and flexible cages to a series of quaternary ammonium ions have been systema... 相似文献
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Lifei Zhi Xiufang Shi Erzhuang Zhang Chuangji Gao Haocheng Gai Hui Wang Zhenmin Liu Tieming Zhang 《Molecules (Basel, Switzerland)》2022,27(7)
A series of double-chain quaternary ammonium salt surfactants N-[N′[3-(gluconamide)] propyl-N′-alkyl]propyl-N,N-dimethyl-N-alkyl ammonium bromide (CnDDGPB, where n represents a hydrocarbon chain length of 8, 10, 12, 14 and 16) were successfully synthesized from D (+)-glucose δ-lactone, N,N-dimethyldipropylenetriamine, and bromoalkane using a two-step method consisting of a proamine-ester reaction and postquaternization. Their surface activity, adsorption, and aggregation behavior in aqueous solution were investigated via measurements of dynamic/static surface tension, contact angle, dynamic light scattering, and transmission electron microscopy. An analysis of their application performance in terms of wettability, emulsifying properties, toxicity, and antibacterial properties was conducted. The results show that with increasing the carbon chain length of the CnDDGPB surfactants, their critical micelle concentration (CMC) increased and the pC20 and efficiency in the interface adsorption of the target product gradually decreased. Moreover, the influence of the hydrophobic carbon chain length on the surface of polytetrafluoroethylene (PTFE) was even greater for the wetting effect, reducing the contact angle to 32° within the length range of C8–C14. The results of the contact angle change and the wettability experiments proved that C10DDGPB exhibited the best wettability. The liquid paraffin and soybean oil emulsification ability of CnDDGPB showed an upward trend followed by a downward trend with the growth of the carbon chain, with C12DDGPB exhibiting the best emulsification performance. The Dlong/Dshort ratio was far lower than 1, which indicates mixed-kinetic adsorption. The surfactants formed spherical micelles and showed a unique aggregation behavior in aqueous solution, which showed an increase–decrease–increase trend with the change in concentration. A cell toxicity and acute oral toxicity experiment showed that the CnDDGPB surfactants were less toxic than the commonly used surfactant dodecyldimethylbenzyl ammonium chloride (1227). In addition, at a concentration of 150 ppm, CnDDGPB exhibited the same bacteriostatic effect as 1227 at a concentration of 100 ppm. The results demonstrate that sugar-based amide cationic surfactants are promising as environmentally friendly disinfection products. 相似文献
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制备了α-二乙氨基苯乙酮并在醋酸环境下将该化合物与苯基缩水甘油醚(PGE)反应合成了以醋酸根为配对阴离子的、具有芳酮结构的光敏性季铵盐(α-PGE-A),通过红外吸收光谱,核磁共振谱及热重分析对α-PGE-A紫外光辐照前后的结构进行了研究。红外光谱显示α-PGE-A经紫外辐照后,其羰基吸收峰显著增强,醋酸根离子吸收峰消失;核磁共振研究表明样品光照后可能生成频胺及醋酸酯。α-PGE-A与环境树脂复配合的热固化研究显示,经紫外光辐照后的样品热固化较易进行完全。表明α-PGE-A具有一定光产碱活性。 相似文献
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绝大多数Schotten-Baumann酰化[1]在两相间发生,为探究在单相水介质中合成酰胺的效率,我们企图对几个典型的羧酸引入四级铵基,以制备结晶的水溶性酰氯. 相似文献
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研究了苄基三甲基溴化铵动态改性、十四烷基吡啶盐等“永久性”涂渍的两种反相色谱,系统分离和间接光度检测了强极性、弱紫外吸收羟基酸。测定这些检测和改性试剂在YWG-CH反相填料和甲醇-磷酸缓冲液色谱体系的吸附等温线,探讨试剂在固定相的吸附量和其它因素对羟基酸保留、检测灵敏度的影响及分离检测机理。 相似文献