摘要：
By using ambient air as an oxidant, various N-acylated 3-aminoquinoxalin-2(1H)-ones were efficiently synthesized through visible-light-promoted rhodamine B-catalyzed amidation reaction of quinoxalin-2(1H)-ones and amides under metal-free and strong oxidant-free conditions.
关键词：
Quinoline N-oxides;2-Sulfonylquinolines;Sodium sulfinates;Sulfonylation;In water
摘要：
An eco-friendly protocol for the synthesis of various 2-sulfonyl quinolines/pyridines through sulfonylation of heteroaromatic N-oxides with sodium sulfinates in water at ambient temperature under metal- and oxidant-free conditions has been developed. The mild reaction conditions, high reaction efficiency, operational simplicity, short reaction time and remarkable functional-group compatibility make the developed protocol very attractive for the preparation of 2-sulfonyl N-heteroaromatic compounds.
作者机构：
[Zhou, Ke; Wu, Hai-Chen; Guo, Bingyuan; Liu, Lei] Chinese Acad Sci, Beijing Natl Lab Mol Sci, Key Lab Analyt Chem Living Biosyst, Inst Chem, Beijing 100190, Peoples R China.;[Zhao, Yuliang; Liu, Lei] Chinese Acad Sci, Key Lab Biomed Effects Nanomat Nanosafety, Inst High Energy Phys, Beijing 100049, Peoples R China.;[You, Yi; Cao, Zhong] Changsha Univ Sci & Technol, Collaborat Innovat Ctr Micro Nano Biosensing & Fo, Sch Chem & Biol Engn, Hunan Prov Key Lab Mat Protect Elect Power & Tran, Changsha 410114, Hunan, Peoples R China.;[Wu, Hai-Chen] Univ Chinese Acad Sci, Beijing 100049, Peoples R China.
通讯机构：
[Wu, Hai-Chen] C;[Wu, Hai-Chen] U;Chinese Acad Sci, Beijing Natl Lab Mol Sci, Key Lab Analyt Chem Living Biosyst, Inst Chem, Beijing 100190, Peoples R China.;Univ Chinese Acad Sci, Beijing 100049, Peoples R China.
关键词：
DNA probe;host-guest systems;nanopore;simultaneous quantification;single-molecule studies
摘要：
Both protease overexpression and local pH changes are key signatures of cancer. However, the sensitive detection of protease activities and the accurate measurement of pH in a tumor environment remain challenging. Here, we develop a dual-response DNA probe that can simultaneously monitor protease activities and measure the local pH by translocation through α-hemolysin (αHL). The DNA probe bears a short peptide containing phenylalanine at a pre-designed position. Enzymatic cleavage of the peptide either exposes or removes the N-terminal phenylalanine that can form a complex with cucurbit[7]uril. Translocation of the DNA hybrid through αHL generates current signatures that can be used to quantify protease activities. Furthermore, the current signatures possess a pH-dependent pattern that reflects the local pH. Our results demonstrate that the versatile DNA probe may be further explored for simultaneously measuring multiple parameters of a complex system such as single cells in the future.
关键词：
Phase change materials;Solar absorption cooling;Thermal energy storage;Thermodynamic properties
摘要：
Phase change materials (PCMs) that can store the heat energy obtained from intermittent solar irradiation are very important for solar energy absorption cooling system. In this work, an organic compound that melts at the temperature of 368.2 +/- 0.5 K was applied as PCM. The specific heat capacities of the PCM were measured by temperature-modulated differential scanning calorimetry from 198.15 to 431.15 K. The thermodynamic functions of [H (T)-H (298.15)] and [S (T)-S (298.15)] were then calculated based on the measured heat capacities data. Afterward, the long-term cyclic thermal energy storage stability and thermal stability of the PCM were investigated. The results show that the PCM melted and crystallized at about 368 and 364 K, respectively, with a phase change enthalpy (Delta(trans) H) of 21 kJ mol(-1) (130 J g(-1)). Additionally, it exhibited good long-term cyclic thermal energy storage stability and thermal stability. Hence, the PCM could be applied as good PCM for solar energy absorption cooling.
通讯机构：
[He, Wei-Min] H;Hunan Univ Sci & Engn, Hunan Prov Engn Res Ctr Ginkgo Biloba, Yongzhou 425100, Peoples R China.
摘要：
A general, effective and convenient protocol for the direct synthesis of various 2-aminoquinolines (39 examples) through AgBF4-catalyzed amination of quinoline N-oxides with isothiocyanates under base-, oxidant-free and mild conditions was developed. The transformation could be performed on a gram-scale and in a sequential manner starting from quinoline N-oxide to the synthesis of benzo[4,5]imidazo[1,2-a]quinoline.
关键词：
AgI/CuFe(2)O(4) photocatalyst;Antibacterial;Magnetic;Reusability and stability;Synergistic effect
摘要：
Magnetic materials usually exhibit advanced performance in many areas for their easy separating and recycle ability. In this study, silver iodide/copper ferrite (AgI/CuFe2O4) catalysts with excellent magnetic property were successfully synthesized and characterized by a series of techniques. Two typical bacteria Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were applied to estimate the photocatalytic inactivation performance of obtained AgI/CuFe2O4 catalysts. Results revealed that the AgI/CuFe2O4 (12.5% AgI) composite could absolutely inactivate 3x10(9) CFU/mL E. coli and 2.7x10(8) CFU/mL S. aureus cells severally in 50min and 40min under visible light irradiation, which showed a much higher photo-disinfection activity than monomers. Transmission electron microscopy was used to study the biocidal action of this nanocatalyst, the results confirmed that the treated E. coli cells were damaged, the nanocatalyst permeated into cells and resulting in death of cells. Besides, it was found that the destruction of bacterial membrane together with substantial leaked potassium ion (K(+)) which caused by the photo-generated reactive species superoxide radical (O2(-)) and holes (h(+)) could be the direct disinfection principles. For a deep insight into practical applications, the influences of different catalyst concentrations and reaction pH were also taken into discussion in details. The overall results indicated the novel photocatalyst with strong redox capacity and outstanding reusability can be widely employed in bacteria elimination.
作者机构：
[He, Wei-Min; Cao, Zhong; Zhu, Qin] Changsha Univ Sci & Technol, Hunan Prov Key Lab Mat Protect Elect Power & Tran, Changsha 410114, Peoples R China.;[Lin, Ying-Wu] Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.;[Zhu, Qin] Hunan Univ Sci & Technol, Dept Chem, Xiangtan 411201, Peoples R China.
通讯机构：
[He, Wei-Min] C;Changsha Univ Sci & Technol, Hunan Prov Key Lab Mat Protect Elect Power & Tran, Changsha 410114, Peoples R China.
关键词：
Green chemistry;Dual role;Quinoline N-oxides;Alkynes;Water
摘要：
Herein we summarized some clean preparation examples to emphasize the concept of dual roles design (or named as "two birds one stone strategy") in green and sustainable chemistry. In those examples, the reactants and/or solvent play dual roles rendering a cleaner organic preparation process. Consequently, both the chemical waste and manufacturing cost could be reduced. (C) 2019 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.
作者机构：
[肖忠良; 池振振; 宋刘斌; 曹忠; 黎安娴] Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation, School of Chemistry and Food Engineering, Changsha University of Science and Technology, Changsha;Hunan;410114, China;[肖忠良; 池振振; 宋刘斌; 曹忠; 黎安娴] Hunan;[肖忠良; 池振振; 宋刘斌; 曹忠; 黎安娴] 410114, China
通讯机构：
[Wang, Jianxiu] C;[Wang, Jianxiu] K;Cent S Univ, Coll Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.;Key Lab Hunan Prov Water Environm & Agr Prod Safe, Changsha 410083, Hunan, Peoples R China.
摘要：
MDM2 can mediate the degradation of tumor suppressor p53 through an autoregulatory feedback loop, in which MDM2 abolishes wild-type p53 function and accelerates malignant transformation. However, the incorporation of MDM2 antagonist Nutlin-3 could reactivate the transcriptional activity of p53, up-regulate caspase-3, and induce apoptosis. In this work, the simultaneous and label-free monitoring of p53-MDM2 complex and caspase-3 levels in cancer cells before and after Nutlin-3 treatment was conducted using dual-channel surface plasmon resonance (SPR). The p53-MDM2 complex was captured in one fluidic channel covered with consensus double-stranded (ds)-DNA, while the other channel was pre-immobilized with caspase-3-specific biotinylated DEVD-containing peptides. To amplify the SPR signals, the attachment of streptavidin (SA)-conjugated anti-MDM2 antibody in both channels was achieved. The signal diversity before and after Nutlin-3 treatment is indicative of the difference in the levels of the intracellular p53-MDM2 complex and caspase-3. The limit of detection for p53-MDM2 and caspase-3 down to 4.54 pM and 0.03 ng mL(-1), respectively, was attained. Upon treatment with Nutlin-3, MCF-7 cancer cells with wild-type p53 showed decreased expression of the p53-MDM2 complex and an increased caspase-3 level, while MDA-MB-231 cancer cells with mutant p53 exhibited an elevated caspase-3 level and unchanged p53-MDM2 complex expression. The apoptosis of MCF-7 and MDA-MB-231 cancer cells upon Nutlin-3 treatment follows a p53-dependent and a p53-independent pathway, respectively. The proposed method is sensitive, selective and label-free, holding great promise for assaying intracellular p53-MDM2 complex and caspase-3 levels and differentiating Nutlin-3-mediated p53-dependent or p53-independent apoptotic pathways.
