CHEMICAL PAPERS
·
2017
·Vol. 72
·期 1
·51-56
·
IF 1.258
Wei Mengyi,Qian Chao,Chen Xinzhi
Based on the recycling of NO
x
, the Cu(I)- and HNO 3 -catalyzed oxidation of 2-chloro-4-(methylsulfonyl)toluene to 2-chloro-4-(methylsulfonyl)benzoic acid has been developed with an excellent yield of 84.2% and a purity of 99.7%. The optimized reaction conditions (160 °C, oxygen pressure 1.5 MPa, HNO 3 concentration 25 wt%, HNO 3 : substrate 0.5:1) use 1.0 mol% CuI as catalyst. The dosage of HNO 3 in the new process is only 25% of the stoichiometric amount and 12.5% of the amount of the traditional process. The NO
x
emission is 5% amount of the traditional process. The oxidation of several additional toluene derivatives with comparable yields demonstrates the generality to these reaction conditions.
研究领域:
化学
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2020
·
IF 4.335
Lujia Mao,Chunlei Li,Libo Xiang,Dejun Fu,Wangyang Ma,Qing Ye
The synthesis of allenyl-Bdan has been realized via the Cu(I)-catalyzed borylation of propargylic alcohols. This methodology offers a facile and efficient pathway toward allenyboronates with diverse functional groups due to the simple access to the substrates. The substrates bearing ester groups are well-tolerated in the synthesis of allenyl-Bdan under the Lewis acidic conditions. The structures of two allenyl-Bdan were further confirmed via single-crystal X-ray diffraction.
研究领域:
有机化学
·
合成化学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2022
·
IF 4.198
Jun Ma,Qijie Zou,Chunhua Wang,Guangwei Yin,Fangyi Li
Herein, we report a base promoted dibromination of enamides using CBr4 as a bromine source to provide expedient access to β,β-dibrominated secondary enamides. Preliminary synthetic application study shows that these novel products can be readily transformed to 5-Br oxazoles via Cu(I) catalyzed intramolecular cyclization in good yields.
研究领域:
有机化学
·
合成化学
✓ 已验证
DOI
PubMed
高影响因子
DYES AND PIGMENTS
·
2021
·
IF 4.889
Shijun Lin,Shuwen Liu,Guofei Dai,Xiaojin Zhang,Fan Xia,Yu Dai
Gold nanoparticles (AuNPs), as one of the major tools of fluorescence-quenching sensors, have been widely used in biochemical analysis through fluorescence resonance energy transfer (FRET) effect. With the development of chemistry and biochemistry, reaction-based fluorescent sensors have attracted increasing attention because of their unique selectivity, high sensitivity and rapid detection. Here we report a click-induced fluorescence-quenching sensor based on AuNPs for detection of copper ion (Cu 2+ ) and ascorbic acid (AA). A fluorescent dye Rhodamine B-(CH 2 CH 2 O) 4 -azide (RB-PEG 4 -N 3 ) is conjugated to the surface of AuNPs via Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) in the presence of Cu 2+ and AA, leading to the fluorescence quenching of Rhodamine B. The sensor responds quickly (within less than 3 min). The fluorescent intensity linearly correlates with the concentration of Cu 2+ in the range of 0–108 μM. The limit of detection (LOD) for Cu 2+ is 5.8 μM. The concentration range for detection of AA is 0–3 mM. The LOD for AA is 0.13 mM. In addition, the application of the sensor is verified by performing detection in real samples such as fresh orange, juice, VC tablet, and lake water. This work expands the application of AuNPs-based fluorescence-quenching sensors for multi-component detection.
研究领域:
化学
·
生物化学
·
纳米技术
·
分析化学
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产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2016
·Vol. 27
·期 9
·9278-9285
·
IF 1.798
Liu Ziyu,Xu Guangliang,Zhang Ming,Xiong Kun,Meng Pingyuan
Cobalt ferrite/reduced graphene oxide (CoFe 2 O 4 /RGO) nanocomposites were initially prepared by the interaction of alkyne-functionalized CoFe 2 O 4 NPs and azide-functionalized graphene oxide (GO–N 3 ) via the Cu (I)-catalyzed click reaction. The morphology and structure of CoFe 2 O 4 /RGO were investigated by means of XRD, FTIR, TGA, TEM, SEM and the electromagnetic parameters were measured by vector network analyzer. For CoFe 2 O 4 /RGO composites with click reaction, the minimum reflection loss could reach −40 dB at 6.8 GHz with a matching thickness of 4.0 mm, and also it had a bandwidth below −10 dB ranging from 5.8 to 8.5 GHz. The CoFe 2 O 4 /RGO composites with click reaction exhibited better microwave absorbing performance than the physical mixture. Furthermore, the covalent ligation between CoFe 2 O 4 NPs and graphene oxide could make the composites have a promising future in electromagnetic wave absorption materials.
研究领域:
材料科学
·
纳米技术
·
电磁材料
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Acta Biomaterialia
·
2019
·
IF 6.638
Jingdong Rao,Ling Mei,Ji Liu,Xian Tang,Sheng Yin,Chunyu Xia,Jiaojie Wei,Dandan Wan,Xuhui Wang,Yashi Wang,Man Li,Zhirong Zhang,Qin He
Autophagy plays a key role in the stress response of tumor cells, which contributes to cancer cell survival and resistance to chemotherapy by degrading cytoplasmic proteins to provide energy and clear the hazardous substances. Therefore, combined treatment of chemotherapeutics and autophagy inhibitors is thought to obtain a desirable antitumor effect. Nanoparticles (NPs) show potential in tumor-targeting drug delivery because of the enhanced permeability and retention (EPR) effect. However, NPs with fixed particle size cannot achieve optimal delivery effect. Herein, a strategy based on Cu (I)-catalyzed click chemistry-triggered aggregation of azide/alkyne-modified micelles was developed for the co-delivery of the chemotherapeutic drug doxorubicin (Dox) and the autophagy inhibitor wortmannin (Wtmn). In vitro experiments showed that the size of micelles increased in a time-dependent manner, which enhanced micelle accumulation in both B16F10 and 4 T1 cells. The fluorescence resonance energy transfer (FRET) experiment and biodistribution study further demonstrated that the aggregation of micelles through click cycloaddition significantly improved the accumulation of drug-loading micelles at the tumor region. Furthermore, the decreased amount of autophagosomes observed by transmission electron microscopy (TEM), the declined expression of LC3-II, and the increased level of p62 by western blotting and immunohistochemistry (IHC) confirmed the obvious inhibition of autophagy induced by Dox/Wtmn co-loaded size-adjustable micelles, which had a synergistic effect in cancer suppression. In addition, the co-loaded size-adjustable micelles showed outstanding cytotoxicity and antitumor effect. Therefore, this strategy effectively suppressed melanoma and breast cancer in mice. Statement of Significance The therapeutic effects of chemotherapy can be limited by autophagy; hence, combined use of autophagy inhibitors with chemotherapeutics achieves desirable anticancer efficacy. In the present study, we designed size-adjustable micelles by modifying the click reaction substrate azide group and the alkyne group on the surface of micelles, and subsequently, the autophagy inhibitor wortmannin and the chemotherapeutic drug doxorubicin were co-loaded. The micelles could aggregate by click reaction at the tumor site when the catalysts were intratumorally injected. The results showed that the size-adjustable micelles achieved efficient drug delivery, penetration, and retention in tumors; through the combined effect of wortmannin-mediated autophagy inhibition and doxorubicin-mediated cytotoxicity, this strategy exerted significant anticancer effect in melanoma and breast cancer treatment.
研究领域:
药学
·
纳米技术
·
肿瘤学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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