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31.
Copperproteinsitesareassociatedwithavarietyofvitalbiologicalfunctions,includingelectrontransfer,anddioxygentransportandactivationl.ThelargemolecularweightandcomPlexnatureoftheproteinsmakedetailedstudiesoftheiractivesitesandchemistryverydifficult-Tobetterunderstandtheinherentcoordinationchemistryassociatedwiththeactivesite,syntheticanalogsaremostuseful2.Histidine(imidazole)playskeyrolesinthecatalyticfunctionsofalmostallofthemetalloenzymes.Therefore,complexeswithinddazoleligandsareofinterestast… 相似文献
32.
Jaehong Kim Sung Heum Park Jinwoo Kim Shinuk Cho Youngeup Jin Joo Young Shim Hyunmin Shin Sooncheol Kwon Il Kim Kwanghee Lee Alan J. Heeger Hongsuk Suh 《Journal of polymer science. Part A, Polymer chemistry》2011,49(2):369-380
Newly designed 2H‐benzimidazole derivatives which have solubility groups at 2‐position have been synthesized and incorporated into two highly soluble carbazole based alternating copolymers, poly[2,7‐(9‐(1′‐octylnonyl)‐9H‐carbazole)‐alt‐5,5‐(4′,7′‐di(thien‐2‐yl)‐2H‐benzimidazole‐2′‐spirocyclohexane)] (PCDTCHBI) and poly[2,7‐(9‐(1′‐octylnonyl)‐9H‐carbazole)‐alt‐5,5‐(4′,7′‐di(thien‐2‐yl)‐2H‐benzimidazole‐2′‐spiro‐4′′‐((2′′′‐ethylhexyl)oxy)‐cyclohexane)] (PCDTEHOCHBI) for photovoltaic application. These alternating copolymers show low‐band gap properties caused by internal charge transfer from an electron‐rich unit to an electron‐deficient moiety. HOMO and LUMO levels are –5.53 and –3.86 eV for PCDTCHBI, and –5.49 and –3.84 eV for PCDTEHOCHBI, respectively. Optical band gaps of PCDTCHBI and PCDTEHOCHBI are 1.67 and 1.65 eV, respectively. The new carbazole based the 2H‐benzimidazole polymers show 0.11–0.13 eV lower values of band gaps as compared to that of carbazole based benzothiadiazole polymer, poly[N‐9′‐heptadecanyl‐2,7‐carbazole‐alt‐5,5‐(4′,7′‐di‐2‐thienyl‐2′,1′,3′‐benzothiadiazole)] (PCDTBT), while keeping nearly the same deep HOMO levels. The power conversion efficiencies of PCDTCHBI and PCDTEHOCHBI blended with [6,6]phenyl‐C71‐butyric acid methyl ester (PC71BM) are 1.03 and 1.15%, respectively. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
33.
P. A. Ramazanova A. V. Tarakanova M. V. Vagabov V. V. Litvinova A. V. Anisimov 《Chemistry of Heterocyclic Compounds》2000,36(2):201-206
The reactions of 2-allylthiobenzimidazole, -oxazole, and-thiazole, and the thiones formed from them on heating, with dichlorocarbene have been investigated under phase transfer catalysis conditions.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 243–248, February, 2000. 相似文献
34.
Lubov' V. Snegur Yury S. Nekrasov Nataliya S. Sergeeva Zhanna V. Zhilina Vera V Gumenyuk Zoya A. Starikova Alexander A. Simenel Nataliya B. Morozova Irina K. Sviridova Valery N. Babin 《应用有机金属化学》2008,22(2):139-147
The toxicity of ferrocenylethyl benzotriazole ( 1 ) and other ferrocene compounds including ferrocenylmethyl benzimidazoles ( 4,5,6,11 ), ferricenium salts ( 3,9,10 ) and ferrocenylmethyl adenine ( 7 ), was studied. All ferrocene complexes under investigation showed low or medium toxicities. On the basis of an earlier model of chemical carcinogenesis, the antitumor activity of ferrocenylalkyl azoles 1, 8 and ferricenium salts 9, 10 was studied in vivo in the so‐called sub‐capsular test on human tumors. This effectiveness was compared with that of cisplatin. A series of ferrocenylalkyl azoles were synthesized by interacting azoles either with α‐hydroxyalkyl ferrocenes FcC(OH)R1R2 in organic solvent in the presence of aqueous HBF4 in quantitative yields or with trimethyl(aminomethyl)ferrocene iodide in an aqueous‐basic medium in good yields. The X‐ray determinations of molecular and crystal structures of α‐(1‐benzotriazolyl)ethylferrocene ( 1 ) and α‐(1‐naphthatriazolyl)ethylferrocene ( 12 ) were performed. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
35.
Guimei Zhang Xiaoxia Guo Jianhua Fang Kangcheng Chen Ken-ichi Okamoto 《Journal of membrane science》2009
A series of sulfonated copolyimides containing benzimidazole groups (SPIs) were synthesized by random copolymerization of 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA), 2-(4-aminophenyl)-5-aminobenzimidazole (APABI), 4,4′-diaminodiphenyl ether-2,2′-disulfonic acid (ODADS) and 9,9-bis(4-aminophenyl)fluorene (BAPF) in m-cresol in the presence of benzoic acid and triethylamine at 180 °C for 20 h. Membranes with good mechanical properties were prepared by solution cast method. Proton exchange treatment resulted in ionic cross-linking and the membranes were further covalently cross-linked by treating them in polyphosphoric acid (PPA) at 180 °C for 6 h. The covalently cross-linked membranes displayed slightly lower ion exchange capacities (IECs) and proton conductivities than the corresponding covalently uncross-linked ones because small part of the sulfonic acid groups had been consumed during the cross-linking process. Fenton’s test (3% H2O2 + 3 ppm FeSO4, 80 °C) revealed that benzimidazole groups played an important role in the radical oxidative stability of the membranes, while the cooperative effect of benzimidazole groups and covalent cross-linking led to much more significant enhancements in the radical oxidative stability of the membranes than each alone. The membrane 4 (ODADS/APABI/BAPF = 2/1/1, by mol), for example, after covalent cross-linking could maintain membrane form within 8 h measurement, which was much longer than that (3 h) before covalent cross-linking under the same conditions. The membrane 5 (ODADS/BAPF = 3/1, by mol) without benzimidazole groups, however, after covalent cross-linking started to break into pieces after 85 min measurement, which was only slightly longer than that (60 min) before cross-linking under the same conditions. 相似文献
36.
Umberto Costantino Maria Antonietta Massucci Aldo La Ginestra Anna Maria Tarola Laura Zampa 《Journal of inclusion phenomena and macrocyclic chemistry》1986,4(2):147-162
The intercalation of imidazole and some organic species containing the imidazole ring, between the layers of crystalline zirconium phosphate has been investigated. Fourteen new, well-ordered intercalation compounds are obtained with the batch procedure at r.t. and/or 60°C. A mechanism of formation of the various compounds is proposed on the basis of the interaction between the guest molecules (with their dimensions and geometries) and the free PO3OH groups available between the layers of the host. The new phases have been characterized by TG and X-ray methods. 相似文献
37.
Synthesis of pyrimido[1,2-a]benzimidazole and pyrano[2,3-c]pyrazole derivatives were achieved using polyethylene glycol (PEG-400) as promoting reaction medium in water under catalyst-free conditions at reflux and room temperature, respectively. The structure of pyrimido[1,2-a]benzimidazole was confirmed using 1H NMR, 13C NMR, DEPT, and HMBC experiments. The promising points for the present methodology are efficiency, generality, high yield, short reaction time, cleaner reaction profile, ease of product isolation, simplicity, potential of recycling reaction medium, and finally agreement with green chemistry protocols. 相似文献
38.
The title compound,[Zn2(H2C4BIm)(ox)2]·2H2O(1,H2C4BIm = 2,2'-(1,4-bu-tanediyl)bis(1H-benzimidazole),has been synthesized by the hydrothermal reaction of Zn(NO3)2·6H2O with H2C4BIm and Na2C2O4 in water solution.It crystallizes in the triclinic system,space group P1 with a = 9.445(9),b = 9.598(9),c = 14.962(14) ,α = 72.160(10),β = 79.905(12),γ = 83.680(11)°,Mr = 633.18,V = 1269(2) 3,Z = 2,Dc = 1.657 g/cm3,F(000) = 644,μ = 1.953 mm-1,the final R = 0.0671 and wR = 0.1689.X-ray crystal structure analysis revealed that 1 is a 3D network with(203)2(20)3 topology in which the ZnII atom can be considered as a 3-connected node and both ox2-and H2C4BIm serve as the linear linkers. 相似文献
39.
《Journal of Coordination Chemistry》2012,65(21):3473-3483
Two Co(II) coordination polymers, [CoL(npa)]·2H2O (1) and [CoL(Hnpa)2] (2) (L = 1,4-bis(5,6-dimethylbenzimidazole-1-yl)benzene, H2npa = 5-nitroisophthalic acid), have been synthesized in different solvent systems and characterized by Infrared (IR) spectroscopy, elemental analysis, and powder and single crystal X-ray diffraction. Compound 1 was synthesized under solvothermal conditions with DMF as solvent and had a pair of L ligands adopting a μ2-bridging mode and connecting two Co2+ cations to generate a 26-membered Co2L2 loop. The npa2? link adjacent Co2L2 loops via a bis(monodentate) bridging mode to create a 1-D channel-like chain structure. Compound 2 was obtained under hydrothermal conditions, and the carboxylate of the monodeprotonated Hnpa? adopt a μ1-η0?:?η1 coordination to connect adjacent Co2+ cations into a 2-D polymeric layer. The μ2-bridging L ligands connect adjacent 2-D [Co(Hnpa)]n polymeric layers into a 3-D NaCl-like framework. The Co2+ cations and the L ligands in compounds 1 and 2 exhibit different coordination geometries and conformations. Effects of solvents on the construction of Co(II) coordination polymers were investigated. In addition, the electrochemical behavior of carbon paste electrodes containing 1 and 2 and the thermal stabilities of 1 and 2 were investigated. 相似文献
40.
Ülkü Yılmaz Hasan Küçükbay Nihat Şireci Mehmet Akkurt Selami Günal Rıza Durmaz M. Nawaz Tahir 《应用有机金属化学》2011,25(5):366-373
A mixture of benzimidazole salts (2–7), Pd(OAc)2 and K2CO3 in DMF–H2O catalyzes the Suzuki–Miyaura cross‐coupling reactions promoted by microwave irradiation resulting in high yield within a short time. In particular, the yield of the Suzuki–Miyaura reactions with aryl bromides was found to be nearly quantitative. The synthesized benzimidazole salts (2–7) were identified by 1H‐13C, NMR, IR spectroscopic methods and microanalysis. The molecular structure of 1 was determined by X‐ray crystallography. The antibacterial and antifungal activities of the novel benzimidazole derivatives (1–7) were also tested against standard strains. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献