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141.
Xingzhong Guo Wenyan Li Hui Yang Kazuyoshi Kanamori Yang Zhu Kazuki Nakanishi 《Journal of Sol-Gel Science and Technology》2013,67(2):406-413
An in situ two-step processing using an initial acid catalysis step accompanied by an epoxide-mediated condensation step in the presence of ammonium chloride (NH4Cl) is reported, and macroporous cocontinuous methylsilsesquioxane (MSQ) monoliths have been successfully prepared by this processing. We explain the hydrolysis, gelation behavior and phase separation of MTMS(methyltrimethoxysilane)-MeOH(methanol)-HCl-PO(propylene oxide) system and the in situ effect of NH4Cl, and examine the macroporous morphology and pore structures of MSQ monoliths obtained under different conditions. Macroporous MSQ monolith under optimized conditions possesses a narrow macropore size distribution between 3 to 10 μm, surface area as high as 366 m2·g?1 and minimal shrinkage of only 1 %. 相似文献
142.
Dian‐Feng Chen Feng Zhao Yue Hu Liu‐Zhu Gong 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(40):10939-10943
A combination of either ruthenium(II) or rhodium(II) complexes and quinine‐derived squaramide enables 3‐diazooxindoles, indoles, and nitroalkenes to undergo highly efficient asymmetric three‐component reactions, thus affording optically active 3,3′‐bis(indole)s through a consecutive C C bond‐forming sequence, which turned out to be applicable to the facile total synthesis of (−)‐folicanthine. 相似文献
143.
A novel Pd-catalyzed intramolecular cyclization via tert-butyl isocyanide insertion from 2-(2-bromophenyl)-1H-indoles has been developed, which demonstrates the utility of isocyanides in C–N or C–C bond construction. Treatment of 2-(2-bromophenyl)-1H-indoles with tert-butyl isocyanide affords 6H-isoindolo[2,1-a]indol-6-ones with high efficiency. However, N-methyl or N-Boc protected 2-(2-bromophenyl)-1H-indoles gives indenoindolones in excellent yields under the same condition, which reveals that under the described situation, isocyanides insertion for the formation of C–N bonds is prior to that of C–C bonds. 相似文献
144.
Chao He Xiaohui Zhang Ruofeng Huang Jing Pan Jiaqiang Li Xuege Ling Yan Xiong Xiangming Zhu 《Tetrahedron letters》2014
Under open-flask conditions, an efficient method to assemble a series of diversely functionalized diarylketones in the presence of commercially available NBS has been developed. Yields of up to 99% have been achieved employing diarylmethanes as starting material. Based on 18O-labeled experiment, the addition of stoichiometric water eventually leads to excellent yields in all carbonylation cases. 相似文献
145.
Peng Chen Zhuyuan Wang Shenfei Zong Hui Chen Dan Zhu Yuan Zhong Yiping Cui 《Analytical and bioanalytical chemistry》2014,406(25):6337-6346
p-Aminothiophenol (pATP) functionalized multi-walled carbon nanotubes (MWCNTs) have been demonstrated as an efficient pH sensor for living cells. The proposed sensor employs gold/silver core-shell nanoparticles (Au@Ag NPs) functionalized MWCNTs hybrid structure as the surface-enhanced Raman scattering (SERS) substrate and pATP molecules as the SERS reporters, which possess a pH-dependent SERS performance. By using MWCNTs as the substrate to be in a state of aggregation, the pH sensing range could be extended to pH 3.0~14.0, which is much wider than that using unaggregated Au@Ag NPs without MWCNTs. Furthermore, the pH-sensitive performance was well retained in living cells with a low cytotoxicity. The developed SERS-active MWCNTs-based nanocomposite is expected to be an efficient intracellular pH sensor for bio-applications. 相似文献
146.
Wangyu Li Mingteng Xiong Xiao Liang Dungai Wang Heping Zhu Prof. Dr. Yuanjiang Pan 《ChemistryOpen》2022,11(1):e202100268
An electro-oxidative cyclization pathway in which hydrazones are selected as starting materials to generate amphiphiles by reacting with benzylamines and benzamides was reported. This strategy successfully prepared a series of 1,2,4-triazoles in satisfactory yields. Moreover, the use of cheap stainless steel as the anode, the feasibility to conduct the transformation as a one-pot reaction and the proof that scaling-up these reactions is possible make this transformation attractive for potential application in industry. 相似文献
147.
Dingzhong Li Wensheng Zhang Dr. Longzhi Zhu Prof. Dr. Shuang-Feng Yin Prof. Dr. Nobuaki Kambe Prof. Dr. Renhua Qiu 《ChemistryOpen》2022,11(5):e202200023
An efficient hydrazine substitution of p-nitro-aryl fluorides with hydrazine hydrates catalyzed by FeO(OH)@C nanoparticles is described. This hydrazine substitutions of p-nitro-aryl fluorides bearing electron-withdrawing groups proceeded efficiently with high yield and selectivity. Similarly, hydrogenations of p-nitro-aryl fluorides containing electron-donating groups also smoothly proceeded under mild conditions. Furthermore, with these prepared aryl hydrazines, some phthalazinones, interesting as potential structures for pharmaceuticals, have successfully been synthesized in high yields. 相似文献
148.
Ning Liang Yuk-Man Li Zouyan He Wangjun Hao Yimin Zhao Jianhui Liu Hanyue Zhu Erika Kwek Ka-Ying Ma Wen-Sen He Zhen-Yu Chen 《Molecules (Basel, Switzerland)》2021,26(12)
Rutin (R) and quercetin (Q) are two widespread dietary flavonoids. Previous studies regarding the plasma cholesterol-lowering activity of R and Q generated inconsistent results. The present study was therefore carried out to investigate the effects of R and Q on cholesterol metabolism in both HepG2 cells and hypercholesterolemia hamsters. Results from HepG2 cell experiments demonstrate that both R and Q decreased cholesterol at doses of 5 and 10 µM. R and Q up-regulated both the mRNA and protein expression of sterol regulatory element binding protein 2 (SREBP2), low-density lipoprotein receptor (LDLR), and liver X receptor alpha (LXRα). The immunofluorescence study revealed that R and Q increased the LDLR expression, while only Q improved LDL-C uptake in HepG2 cells. Results from hypercholesterolemia hamsters fed diets containing R (5.5 g/kg diet) and Q (2.5 g/kg diet) for 8 weeks demonstrate that both R and Q had no effect on plasma total cholesterol. In the liver, only Q reduced cholesterol significantly. The discrepancy between the in vitro and in vivo studies was probably due to a poor bioavailability of flavonoids in the intestine. It was therefore concluded that R and Q were effective in reducing cholesterol in HepG2 cells in vitro, whereas in vivo, the oral administration of the two flavonoids had little effect on plasma cholesterol in hamsters. 相似文献
149.
Cai Mengmeng Yao Lijuan Zhu Man Tao Peng Nan Ruihua Jian Zengyun 《Journal of Thermal Analysis and Calorimetry》2021,143(4):2911-2918
Journal of Thermal Analysis and Calorimetry - Differential scanning calorimetry was used to investigate the non-isothermal crystallization kinetics of the Fe76.5Nb3B20Cu0.5 glassy alloys. The... 相似文献
150.
Nan Zhao Huawei Mou Yuguang Zhou Xinxin Ju Shoujun Yang Shan Liu Renjie Dong 《Molecules (Basel, Switzerland)》2021,26(4)
Developing a green and sustainable method to upgrade biogas wastes into high value-added products is attracting more and more public attention. The application of solid residues as a performance enhancer in the manufacture of biofilms is a prospective way to replace conventional plastic based on fossil fuel. In this work, solid digestates from the anaerobic digestion of agricultural wastes, such as straw, cattle and chicken manures, were pretreated by an ultrasonic thermo-alkaline treatment to remove the nonfunctional compositions and then incorporated in plasticized starch paste to prepare mulching biofilms by the solution casting method. The results indicated that solid digestate particles dispersed homogenously in the starch matrix and gradually aggregated under the action of a hydrogen bond, leading to a transformation of the composites to a high crystalline structure. Consequently, the composite biofilm showed a higher tensile strength, elastic modulus, glass transition temperature and degradation temperature compared to the pure starch-based film. The light, water and GHG (greenhouse gas) barrier properties of the biofilm were also reinforced by the addition of solid digestates, performing well in sustaining the soil quality and minimizing N2O or CH4 emissions. As such, recycling solid digestates into a biodegradable plastic substitute not only creates a new business opportunity by producing high-performance biofilms but also reduces the environmental risk caused by biogas waste and plastics pollution. 相似文献