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91.
A new series of pyrido[1,2-α]benzimidazole derivatives bearing the aryloxypyrazole nucleus have been synthesized by base-catalyzed cyclocondensation reaction through multi-component reaction(MCR) approach.All the synthesized compounds were investigated against a representative panel of pathogenic strains using broth microdilution minimum inhibitory concentration(MIC) method for their in vitro antimicrobial activity.Reviewing the data,majority of the compounds were found to be active against employed pathogens.SAR study explores that antimicrobial activity is strongly depends on the nature of the substituents at the ether linked aryl ring attached to the pyrazole unit,together with the substituent present on the C5 of the benzimidazole unit. 相似文献
92.
以邻苯二胺、丙二酸和果糖为主要原料,经Knoevenagel反应合成了一个新的芳稠杂环化合物——1,1-二(苯并咪唑-2-基)-2-(喹喔啉-2-基)乙烯(4),收率78.61%,其结构经1H NMR,IR和元素分析表征。利用UVVis和FL研究了4的光学性能,结果表明:4的最大吸收峰位于259 nm和383 nm;在320 nm激发波长激发下,4的λem位于495 nm,具有显著的日光紫外线吸收性能;TG/DTA分析表明:4的熔点为320℃,初始分解温度为402℃,具有良好的热稳定性。 相似文献
93.
Mohan Lakshmi Punna Rao Alapati Sridhar Rao Abburi Saratchandra Babu Mukkamala M. Krishnaji Rao 《合成通讯》2013,43(21):2436-2443
An easy and efficient one-pot condensation method for the synthesis of substituted benzimidazoles from θ-phenylenediamines with aryl aldehydes using urea hydrogen peroxide (UHP) and I2 in dimethylsulfoxide (DMSO) provides wide substrate scope with good to excellent yields and simple and quick isolation of the products. 相似文献
94.
燃料电池用磺化聚酰亚胺质子交换膜材料的制备与性质 总被引:2,自引:0,他引:2
以联萘二酐、磺化二胺和含咪唑基团的非磺化二胺单体为原料,制备了一系列高相对分子质量的磺化聚酰亚胺,该类聚合物具有优异的溶解性和良好的成膜性.得到的质子交换膜具有优异的水解稳定性.苯并咪唑碱性基团的存在提高了磺化聚酰亚胺质子交换膜膜的溶胀稳定性和热稳定性、降低了膜的甲醇透过率.质子导电率测试结果表明,IEC值为2.55mequiv·g-1的膜室温条件下的质子导电率为0.121 S·cm-1,高于在相同测试条件下Nafion 117膜的质子导电率(0.09 S·cm-1). 相似文献
95.
Unique Fluorogenic Ratiometric Fluorescent Chemodosimeter for Rapid Sensing of CN− in Water 下载免费PDF全文
Dr. Ajit Kumar Mahapatra Kalipada Maiti Saikat Kumar Manna Rajkishor Maji Chitrangada Das Mukhopadhyay Bholanath Pakhira Prof. Sabyasachi Sarkar 《化学:亚洲杂志》2014,9(12):3623-3632
A new benzimidazole‐spiropyran conjugate chemosensor molecule ( BISP ) has been synthesized and characterized by 1H NMR spectroscopy, mass spectrometry (ESI‐MS), and elemental analysis. The two isomeric forms ( BISP ? BIMC ) were shown to be highly selective and sensitive to CN? among the ten anions studied in aqueous HEPES buffer, as shown by fluorescence and absorption spectroscopy and even by visual color changes, with a detection limit of 1.7 μM for BIMC . The reaction of CN? with BIMC was monitored by 1H NMR spectroscopy, high‐resolution mass spectrometry (HRMS), UV/Vis measurements, and fluorescence spectroscopy in HEPES buffer of pH 7.4. TDDFT calculations were performed in order to correlate the electronic properties of the chemosensor with its cyanide complex. Further, titration against thiophilic metal ions like Au3+, Cu2+, Ag+, and Hg2+ with [ BIMC‐CN ] in situ showed that it acts as a secondary recognition ensemble toward Au3+ and Cu2+ by switch‐on fluorescence. In addition, a reversible logic‐gate property of BIMC has been demonstrated through a feedback loop in the presence of CN? and Au3+ ions, respectively. Furthermore, the use of BIMC to detect CN? in live cells by fluorescence imaging has also been demonstrated. Notably, test strips based on BIMC were fabricated, which could serve as convenient and efficient CN? test kits. 相似文献
96.
Syntheses,Structures, and Catalytic Properties of Two 2D Manganese(II) Coordination Polymers Containing Flexible Bis(benzimidazole) Ligands 下载免费PDF全文
Two MnII coordination polymers based on the flexible bis(benzimidazole) and dicarboxylic acids, namely, [Mn(L1)(bpdc)(H2O)0.5]n ( 1 ) and [Mn(L2)(Htbi)2]n ( 2 ) [L1 = 1,4‐bis(5,6‐dimethylbenzimidazol‐1‐ylmethyl)benzene, H2bpdc = 4,4′‐biphenyldicarboxylic acid, L2 = 1,4‐bis(5,6‐dimethylbenzimidazole)butane, H2tbi = 5‐tert‐butyl isophthalic acid] were hydrothermally synthesized and characterized by elemental analysis, IR spectroscopy, as well as single‐crystal X‐ray diffraction. Both of the complexes crystallize in the triclinic P$\bar{1}$ space group and present distorted octahedral configurations. Complex 1 possesses a 2D binodal (3,5)‐connected 3,5L2 network with the point symbol of (42.67.8)(42.6), whereas 2 features a 2D uninodal 3‐connected hcb topology and the Schläfli symbol is (63). Complexes 1 and 2 ultimately are extended into 3D supramolecular framework via π–π stacking and O–H ··· O hydrogen bonding interaction, respectively. Moreover, both of the complexes manifest excellent catalytic activities for the degradation of Congo red. 相似文献
97.
Tuning Cadmium Coordination Architectures by Phenylenediacetate Position Isomers and 1,4‐Bis(benzimidazol‐1‐ylmethyl)benzene 下载免费PDF全文
Three position isomers 1,2‐, 1,3‐, 1,4‐phenylenediacetate and 1,4‐bis(benzimidazol‐1‐ylmethyl)benzene (bmb) were used to assembly cadmium(II) coordination polymers, [Cd(bmb)(1,2‐phda)]n ( 1 ), {Cd(bmb)(1,3‐phda)] · 0.5(bmb)}n ( 2 ), and [Cd(bmb)0.5(1,4‐phda)]n ( 3 ), which are characterized by elemental analyses, infrared spectra (IR), thermogravimetric analysis (TGA) and single‐crystal X‐ray diffraction. Single crystal structure analysis shows that complex 1 is a two‐dimensional wave‐like layer network. Complex 2 features a (3,5)‐connected three‐dimensional frameworks with (42.6)(42.65.83) topology, whereas complex 3 shows a (4,4)‐connected three‐dimensional (4.64.7)(42.62.82) topology. The structural versatility reveals that a significant structure‐directing effect of the position of the acetate groups during self‐assembly of these coordination polymers. Moreover, luminescent properties and thermal stabilities of three complexes were discussed in detail. 相似文献
98.
合成了15种新型三脚架结构苯并咪唑季铵盐类化合物(3a~3o)。 通过IR、NMR和HRMS等技术手段对目标产物(3a~3o)进行了结构表征。 并对目标化合物调节植物生长活性进行了评价。 结果表明, 目标化合物浓度为10 mg/L时, 化合物3a、3c、3f、3g、3h、3i和3j均具有优良的促细胞分裂活性, 最高达88.3%, 比参照物三唑酮(50.2%)的促细胞分裂活性更高, 但生长素活性不明显;目标化合物均具有优异的除草活性, 其中化合物3i效果最明显, 可以达到95.6%。 同时利用荧光光谱, 探究了4种代表性目标分子对人体中常见的6种阴离子的荧光识别, 结果发现目标化合物能较好的识别I- , 可作为I-荧光识别探针。 相似文献
99.
100.
Ai‐Guo Li Qi‐Kui Liu Yan‐An Li Zhi‐Xian Liu Yu‐Bin Dong 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(1):37-42
A new 2,2′‐bi‐1H‐benzimidazole bridging organic ligand, namely 1,1′‐bis(pyridin‐4‐ylmethyl)‐2,2′‐bi‐1H‐benzimidazole, C26H20N6, L or (I), has been synthesized and used to create three new one‐dimensional coordination polymers, viz.catena‐poly[[dichloridomercury(II)]‐μ‐1,1′‐bis(pyridin‐4‐ylmethyl)‐2,2′‐bi‐1H‐benzimidazole], [HgCl2(C26H20N6)]n, (II), and the bromido, [HgBr2(C26H20N6)]n, (III), and iodido, [HgI2(C26H20N6)]n, (IV), analogues. Free ligand L crystallizes with two symmetry‐independent half‐molecules in the asymmetric unit and each L molecule resides on a crytallographic inversion centre. In structures (II)–(IV), the L ligand is also positioned on a crystallographic inversion centre, whereas the Hg centre resides on a crystallographic twofold axis. Compound (I) adopts an anti conformation in the solid state and forms a two‐dimensional network in the crystallographic bc plane viaπ–π and C—H...π interactions. The three HgII coordination complexes, (II)–(IV), have one‐dimensional zigzag chains composed of L and HgX2 (X = Cl, Br and I), and the HgII centres are in a distorted tetrahedral [HgX2N2] coordination geometry. Complexes (III) and (IV) are isomorphous, whereas complex (II) displays an interesting conformational difference from the others, i.e. a twist in the flexible bridging ligand. 相似文献