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1.
Russian Journal of Organic Chemistry - Methods have been reported for the preparation of ω-functionalized alkyl maltoside and glycoside detergents via a simple and inexpensive synthetic route....  相似文献   
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The structure and properties of amides are of tremendous interest in organic synthesis and biochemistry. Traditional amides are planar and the carbonyl group non-electrophilic due to nN→π*C=O conjugation. In this study, we report electrophilicity scale by exploiting 17O NMR and 15N NMR chemical shifts of acyclic twisted and destabilized acyclic amides that have recently received major attention as precursors in N-C(O) cross-coupling by selective oxidative addition as well as precursors in electrophilic activation of N-C(O) bonds. Most crucially, we demonstrate that acyclic twisted amides feature electrophilicity of the carbonyl group that ranges between that of acid anhydrides and acid chlorides. Furthermore, a wide range of electrophilic amides is possible with gradually varying carbonyl electrophilicity by steric and electronic tuning of amide bond properties. Overall, the study quantifies for the first time that steric and electronic destabilization of the amide bond in common acyclic amides renders the amide bond as electrophilic as acid anhydrides and chlorides. These findings should have major implications on the fundamental properties of amide bonds.  相似文献   
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Journal of Solid State Electrochemistry - Protonic ceramic fuel cells have become extremely interesting due to their high power output at the intermediate temperature range...  相似文献   
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An efficient domino transformation using a phenyliodine(III) diacetate (PIDA)/I2 combination towards Morin 1,4-thiazine compounds has been developed starting from N,S-acetals. The latter leads to “one-step” regioselective methylene insertion without the need for traditional sulfoxide intermediates in good yields. The reaction involves easily accessible N,S-acetals obtained from cost-effective basic ketones and cysteamine as starting materials. This process ultimately leads to 1,4-thiazines related to natural product and fused derivatives necessary for further QSAR study.  相似文献   
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Here, we reported on a one‐step fabrication of magnetite Fe3O4 nanoparticles/indium tin oxide (ITO) electrode based on the direct growing of Fe3O4 nanoparticles on the ITO surface by using a solvothermal process. The modified electrode was used as electrochemical methotrexate (MTX) biosensor with high sensitivity based on cyclic voltammetry and square wave voltammetry techniques. The results demonstrated a linear relationship between the MTX concentration and its oxidation current peak over a wide range from 10?5 to 10?14 mole/L with a limit of detection of 0.4×10?15 M based on the square wave voltammetry (SWV) technique. In addition, Fe3O4/ITO electrode showed a good capability for measuring very low concentrations of MTX drug dissolved in human serum solution. Also, Fe3O4/ITO electrode was used for detecting MTX in blood serum samples collected from patients after their treatment with MTX. The prepared electrode showed the higher sensitivity that higher than the Viva‐E instrument, which opens the door for developing a cheap, simple and higher sensitive MTX sensor.  相似文献   
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