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An improved and scalable process for substituted 3,8-diazabicyclo[3.2.1]octane was developed.N-Benzyl-2,5-dicarbethoxy-pyrrolidine 2 was reduced to N-benzyl-2.5-dihydroxymethylpyrrolidine 9 and subsequently debenzylated to afford N-Boc-2,5- dihydroxymethylpyrrolidine 10.After mesylation of the diol 10 and cyclization with benzylamine,a diversity of scaffold,3,8- diazabicyclo[3.2.1]octane analogue 12 was obtained in a total yield of 42%in five steps. 相似文献
33.
Room‐Temperature Synthesis of Covalent Organic Frameworks with a Boronic Ester Linkage at the Liquid/Solid Interface 下载免费PDF全文
Chunhua Liu Yanxia Yu Prof. Dr. Wei Zhang Prof. Dr. Qingdao Zeng Prof. Dr. Shengbin Lei 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(51):18412-18418
With various prospected applications in the field of nanoelectronics and catalysis, on‐surface synthesis of single‐layer covalent organic frameworks (surface COFs) with designable structures and properties have attracted enormous interest. Herein, we report on a scanning tunneling microscopic investigation of the surface‐confined synthesis of a covalently bonded boronic ester network directly at the octanoic acid/ highly oriented pyrolytic graphite(HOPG) interface under room temperature. The dynamic reaction process was investigated in detail. STM results indicate that the surface networks undergo structural evolution from a hybrid covalent/noncovalent multiwall porous network to single‐wall hexagonal COF with the decrease of monomer concentration. Further experimental observation disclosed that the boronic ester‐linked system is sensitive to instantaneous voltage pulses and the stimulation of the STM tip. In addition, the 1H NMR spectra has further confirmed that the surface and octanoic acid may play important roles in promoting the reaction between 4,4′‐phenylazobenzoyl diboronic acid (ABBA) and 2,3,6,7,10,11‐hexahydroxytriphenylene (HHTP) building units. 相似文献
34.
利用一步电沉积法,以含有环氧基团的γ-环氧丙氧丙基三甲氧基硅烷(GPTMS)为无机杂化试剂和功能性交联试剂,通过壳聚糖(Chitosan,CS)、辣根过氧化物酶(HRP)和葡萄糖氧化酶(GOD)分子中-NH2与环氧基团的反应,在金电极表面原位制备交联型有机-无机生物杂化膜,得到共固定HRP和GOD的新型双酶生物传感器.实验证实了这种有机-无机生物杂化膜在不同酸、碱条件下都具有高的稳定性和耐用性,克服了CS酸溶的不足,从而扩大了其使用范围.在葡萄糖检测中,交联型双酶传感器HRP-GOD/GPTMS/CS,Au比无交联的双酶传感器HRP-GOD/CS/Au具有更高的灵敏度、更宽的线性范围,其线性范围为1μmol/L-351μmol/L,检期4限为0.3μmol/L. 相似文献
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Corrosion inhibition and mechanism of mild steel in hydrochloric acid by ceftriaxone and amoxicillin
PANG XueHui GONG Min ZHANG YuXuan WEI Qin & HOU BaoRong Institute of Oceanology Chinese Academy of sciences Qingdao China College of Materials Chemical Engineering Sichuan University of Science & Engineering Zigong China School of Chemistry Engineering University of Jinan Jinan China 《中国科学B辑(英文版)》2011,(9)
Corrosion inhibition of mild steel in 1 mol/L HCl by amoxicillin and ceftriaxone in the concentration range of 1.00×10-5-1.00×10-2 mol/L has been studied using weight loss,electrochemical potentiodynamic polarization,electrochemical impedance spectroscopy(EIS),scanning electron microscopy(SEM) and quantum chemistry tests at 298 K.The weight loss experiment showed that the inhibition efficiency increased with amoxicillin and ceftriaxone concentrations to attain the maximums of 80.3% and 94.1%,respectively at... 相似文献
37.
FU YuBin ZHAO ZhongKai LIU Jia LI KuiZhong XU Qian & ZHANG ShaoYun Institute of Materials Science Engineering Ocean University of China Qingdao China 《中国科学B辑(英文版)》2011,(5)
A unique sulfonated polyaniline/vanadate composite was synthesized and utilized as a composite anode in microbial fuel cells on ocean floor (BMFCs). X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were employed to characterize its chemical composition and morphology. Wettability of the composite anodes decreases due to the addition of polytetrafluoroethylene (PTFE). The electrochemical behavior of the composite anodes was investigated by means of linear sweep voltammetry and Tafel plot measurem... 相似文献
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聚硫堇/过氧化氢光致电化学敏感界面的构建及其对葡萄糖氧化酶催化活性的测定 总被引:1,自引:0,他引:1
将具有光电活性的硫堇电聚合在光透电极的表面,制备了聚硫堇膜光电极,利用该电极同时具有光敏和电子受体的性能,使其与葡萄糖氧化酶对葡萄糖催化反应产生的电子供体(过氧化氢)发生光致电化学反应,通过检测由此产生的光电流实现对蛋白质催化活性的检测.本文探讨了聚硫堇/过氧化氢光致电化学敏感界面的响应机理,讨论了偏压、电解质溶液pH和底物浓度对光致电化学反应和测定葡萄糖氧化酶催化活性的影响.通过测定商品葡萄糖氧化酶的催化活性,验证了方法的可行性.应用该敏感界面检测蛋白质的催化活性不需要过氧化物酶,比光度法经济、简便和快速. 相似文献
40.
In the presence of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride(EDC)and N-hydroxysuccinimide(NHS), carboxylic group-functionalized single-walled carbon nanotubes(SWNTs)were assembled vertically on the glassy carbon electrode using ethylenediamine as linking agent to fabricate an aligned electrode(SWNTE).The morphological characteristic was studied with atomic force microscope(AFM)and its electrochemical property was investigated using K_3[Fe(CN)_6]as probe. ssDNA had a sensitive voltammetr... 相似文献