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1.
Sulfonylguanidines are interesting bioactive compounds with a broad range of applications in the treatment of different pathologies. 2-Aminobenzazole-based structures are well employed in the development of new anticancer drugs. Two series of novel N-benzazol-2-yl-N′-sulfonyl guanidine derivatives were synthesized with the sulfonylguanidine in either an extra- or intracyclic frame. They were evaluated for their antiproliferative activity against malignant melanoma tumor cells, thus allowing structure-activity relationships to be defined. Additionally, NCI-60 screening was performed for the best analogue to study its efficiency against a panel of other cancer cell lines. The stability profile of this promising compound was then validated. During the synthetic process, an unexpected new deamidination of the sulfonylguanidine towards sulfonamide function was also identified.  相似文献   
2.
Novel heat‐resistant N‐substituted poly(benzimidazole imide)s (PBIIs) with good solubility were synthesized via a C ? N coupling reaction. A model reaction was carried out to assist in determining the optimal reaction conditions for the polymerization and to elucidate the chemical structures of the polymers. The structures of the resulting polymers were characterized by means of Fourier transform infrared and elemental analysis; the results showed good agreement with the proposed structures. The resulting PBIIs exhibited high glass transition temperatures (Tg > 290 oC) and good thermostability (T5% > 440 oC). The thermal behavior in air of the PBII polymers suggests that they can be considered as a new class of high performance polyimides. © 2016 Society of Chemical Industry  相似文献   
3.
Proton conducting polymer electrolyte membranes were produced by blending of poly(2,5‐benzimidazole) (ABPBI) and poly(2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid) (PAMPS) at several stoichiometric ratios with respect to polymer repeating units. The membranes were characterized by using Fourier transform infrared spectroscopy for interpolymer interactions and scanning electron microscope for surface morphology. Thermal stability of the materials was investigated by thermogravimetric analysis. Glass transition temperatures of the samples were measured via differential scanning calorimetry. The spectroscopic measurements and water uptake studies indicate a complexation between ABPBI and PAMPS that inhibited polymer exclusion up on swelling in excess water. Proton conductivities of the anhydrous and humidified samples were measured using impedance spectroscopy. The proton conductivity of the humidified ABPBI:PAMPS (1 : 2) blend showed a proton conductivity of 0.1 S/cm, which is very close to Nafion 117, at 20°C at 50% relative humidity. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
4.
张宗磊  张燕  吴过  孙倩  王存德 《化学世界》2011,52(6):349-351,361
采用三甲基氯硅烷(TMSCl)作为路易斯催化剂催化芳醛和邻苯二胺合成了2-芳基苯并咪唑化合物.以苯甲醛和邻苯二胺的反应为模型反应,考察了催化剂与反应底物质量比、反应温度和反应溶剂对反应效果的影响,验证了三甲基氯硅烷对合成反应的催化作用.实验结果表明,三甲基氯硅烷能大大加快芳醛和邻苯二胺合成2-芳基苯并咪唑反应的进行,其...  相似文献   
5.
以邻苯二胺和溴代乙酸乙酯为原料一步合成了2-溴甲基苯并咪唑和3,4-二氢-1H-喹喔啉-2-酮.研究结果表明,这两种物质的生成具有伴生性.  相似文献   
6.
7.
李智鹏  扈艳红  杜磊  刘冬冬 《表面技术》2014,43(4):17-23,42
目的研究国产芳纶纤维DAF-III表面上浆剂的主要成分及其对复合材料界面性能的影响。方法用丙酮溶剂抽提纤维一定时间,分析对比去除上浆剂前后的纤维和抽提溶液,并制备DAF-III增强的聚三唑树脂复合材料,测试复合材料的力学性能。结果国产DAF-III芳纶纤维的主体结构是聚酰胺苯并咪唑,表面上浆剂主要组分是脂肪族酯类低聚物。溶剂抽提去除了纤维表面大部分上浆剂,裸露的纤维本体存在制备过程中形成的沿纤维方向的大量沟壑;去除上浆剂后,复合材料的ILSS和弯曲强度分别提高了181.2%和56.20%。结论纤维表面上浆剂对纤维以及纤维增强的复合材料力学性能影响显著,纤维与树脂通过机械锚合和氢键作用改善界面粘接。  相似文献   
8.
苯并咪唑类没食子酸酯(BG)是本实验室合成的、新的抗菌化合物。本文选择了其中已经XRD确定了结构的1-没食子酸乙酯-2-(对溴)苯氧甲基苯并咪唑(BG-Br)为代表进行研究。用BG-Br乳液和BG-Br二甲亚砜溶液分别处理蓝湿皮,采用抑菌圈法和振荡法测定处理皮样的抗菌效果;将BG-Br乳液和BG-Br溶液分别与皮粉作用,对处理皮粉进行DSC分析;观察BG-Br在明胶凝胶中的渗透情况。结果表明,BG-Br的最小抑菌浓度范围为8×10-5~4×10-4g/m L,处理的皮革有较好的抗菌效果;在明胶中的渗透性较好,但处理的铬皮粉的热稳定性会有所下降。总之,这种新的材料有可能在皮革工业上应用,以制备具有一定抗菌性能的皮革。  相似文献   
9.
Three dinuclear coordination complexes generated from 1-n-butyl-2-((5-methyl-1H-pyrazole-3-yl)methyl)-1H-benzimidazole ( L ), have been synthesized and characterized spectroscopically and structurally by single crystal X-ray diffraction analysis. Reaction with iron(II) chloride and then copper(II) nitrate led to a co-crystal containing 78 % of [Cu(NO3)(μ-Cl)( L’ )]2 ( C1 ) and 22 % of [Cu(NO3)(μ-NO3)( L’ )]2 ( C2 ), where L was oxidized to a new ligand L . A mechanism is provided. Reaction with copper chloride led to the dinuclear complex [Cu(Cl)(μ-Cl)( L) ]2 ( C3 ). The presence of N−H⋅⋅⋅O and C−H⋅⋅⋅O intermolecular interactions in the crystal structure of C1 and C2 , and C−H⋅⋅⋅N and C−H⋅⋅⋅Cl hydrogen bonding in the crystal structure of C3 led to supramolecular structures that were confirmed by Hirshfeld surface analysis. The ligands and their complexes were tested for free radical scavenging activity and ferric reducing antioxidant power. The complex C1 / C2 shows remarkable antioxidant activities as compared to the ligand L and reference compounds.  相似文献   
10.
以邻苯二胺和水杨醛为原料合成了2-(5-((3-(1H-苯并[d]咪唑-2基)-4-羟基苯基)甲叉基)-4-氧-2-硫代噻唑-3-基)乙酸。其结构通过红外光谱、核磁共振氢谱和质谱进行了表征,并进行了紫外和荧光性质测定。通过测定甲醇溶液中15种金属离子对该化合物荧光性质的影响,发现钴离子对该化合物的荧光有优于其他金属离子的淬灭效果。表明该化合物对钴离子有较好的选择性,可作为钴离子的淬灭型荧光传感器做进一步的研究。  相似文献   
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