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211.
A new, fast, solvent-free and efficient method is provided to prepare thioformamides by reacting isocyanides derivatives, carbon disulfide and benzylamine under microwave irradiation.  相似文献   
212.
《合成通讯》2013,43(15):2613-2617
Abstract

Cross-coupling reactions of diaryl ketones with imines promoted by ytterbium metal were described. β-Amino alcohols were prepared in good yields under mild and neutral conditions.  相似文献   
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A new ternary composite of 1T-molybdenum disulfide, hexagonal tungsten trioxide, and reduced graphene oxide (M-W-rGO) is synthesized by using a one-pot hydrothermal process. The synergetic effect of 1T-MoS2 and hexa-WO3 nanoflowers improves the electrochemical performance for supercapacitors by inducing additional active sites and hexagonal tunnels, respectively, which lead to high storage capacity and easy transfer of electrolyte ions. The ternary M-W-rGO composite has a high specific capacitance of 836 F g−1 at 1 A g−1, which is nearly twice that of binary composites of M-rGO and W-rGO with high capacitance retention of 86.35 % after 3000 cycles at a high current density of 5 A g−1. This study provides a new ternary composite that can be used as an electrode material for high-performance supercapacitors.  相似文献   
215.
Regeneration of the hoof keratin from ionic liquids was never successful in the past because the ionic liquids were not strong enough. However, this biomaterial starts to play a central role for the preparation of biofilms in the future. In the present study, hoof keratin was regenerated for the first time from an ionic liquid by experiment and characterized by FTIR spectroscopy, Differential Scanning Calorimetry (DSC) and Scanning Electron Microscopy (SEM). As 1-Ethyl-3-methylimidazolium acetate is strong enough to dissolve hooves, which have a lot of disulfide bonds, a Molecular Dynamics (MD) simulation was performed with this ionic liquid and diphenyl disulfide. The MD simulation reveals that not only the cation as postulated after experiments were carried out, but also the anion is very important for the dissolution process. This complete picture was and is not accessible via experiments and is therefore valuable for future investigations. The anion always interacts with the disulfide bond, whereas the cation prefers in some situations a strong H−O interaction with the anion. If the cations and the anions are separated from each other so that the cation can not interact with the anion, both interact with the disulfide bond. The high solvation power of this solvent is shown by the fact that the cation interacts from the left and right side and the anion from above and below the disulfide bond.  相似文献   
216.
We designed, synthesized, and characterized a tri-block copolymer. Its hydrophobic part, a chain of histone deacetylase inhibitor (HDACi) prodrug, was symmetrically flanked by two identical PEG blocks, whereas the built-in HDACi was a linear molecule, terminated with a thiol at one end, and a hydroxyl group at the other. Such a feature facilitated end-to-end linkage of prodrugs through alternatively aligned disulfides and carbonates. The disulfides served dual roles: redox sensors of smart nanomedicine, and warheads of masked HDACi drugs. This approach, carefully designed to benefit both control-release and efficacy, is conceptually novel for optimizing drug units in nanomedicine. Micelles from this designer polyprodrug released only PEG, CO2 and HDACi, and synergized with DOX against HCT116 cells, demonstrating its widespread potential in combination therapy. Our work highlights, for the first time, the unique advantage of thiol-based drug molecules in nanomedicine design.  相似文献   
217.
Layered MoS2@graphene functionalized with nitrogen-doped graphene quantum dots (MoS2@NGQDs-GR) was obtained by one-pot hydrothermal method, as an enhanced electrochemical hydrogen evolution catalyst.  相似文献   
218.
An efficient route for the synthesis of gem-bis(dithiocarbamate) derivatives is developed using dithiocarbamic acid salts generated from primary aliphatic amines and CS2. The method offers high yields, employs mild reaction conditions, and demonstrates excellent functional group compatibility. The structures of the products were confirmed spectroscopically and by X-ray analysis.  相似文献   
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以钨酸钠和半胱氨酸为原料, 采用水热法一步合成了具有超小粒径(约2 nm)的二硫化钨荧光量子点(WS2 QDs). 利用透射电子显微镜(TEM)、 荧光光谱、 X射线光电子能谱(XPS)、 红外光谱(FTIR)和X射线衍射光谱(XRD)对其进行了表征, 并考察了其稳定性和细胞毒性. 结果表明, 制备的WS2 QDs具有水溶性好、 稳定性高和细胞毒性低的优点. 将此WS2 QDs用于人乳腺癌细胞(MCF-7)的成像, 并通过溶酶体荧光探针进行共定位, 发现此WS2 QDs可能借助溶酶体进入细胞内.  相似文献   
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