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991.
The efficient in‐situ reduction and cyclization reaction of aromatic aldehyde, 1,3‐cyclopentanedione (tetronic acid), and nitro‐compound under SnCl2·2H2O‐THF medium 下载免费PDF全文
An efficient in‐situ reduction and cyclization reaction for the synthesis of pyrazolo[4,3‐f]quinoline, pyrazolo[3,4‐f]quinoline, and pyrazolo[3,2‐f]quinoline derivatives directly form 5‐nitroindazole, 6‐nitroindazole and 5‐nitroindole in the presence of SnCl2·2H2O was reported. Compared to traditional synthetic methods, this approach has the advantages of stable reagents, easy obtaining raw material, and high yields. In this research, SnCl2·2H2O is the efficient reducing agent for the in‐situ reduction and cyclization reaction of nitro‐compound. In addition, this process provided an alternative approach for the synthesis of target compounds. 相似文献
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993.
Quantitative study of cellular heterogeneity in doxorubicin uptake and its pharmacological effect on cancer cells 下载免费PDF全文
Bin Deng Zhi‐Ming Wang Zi‐Hao Zhou Yi‐Meng Liu Xi‐Liang Yang Jian Song Yu‐Xiu Xiao 《Biomedical chromatography : BMC》2014,28(10):1393-1401
Cellular heterogeneity in doxorubicin (DOX) uptake and its relationship with pharmacological effect on cancer cells were quantitatively investigated for the first time. An in vitro experimental model was established by treating human leukemia K562 and breast cancer MCF‐7 cells with different schedules of DOX with or without surface P‐glycoprotein (P‐gp) inhibitor verapamil (VER). The cellular heterogeneity in DOX uptake was quantitatively examined by single‐cell analysis using capillary electrophoresis coupled with laser‐induced fluorescence detection. The corresponding cytotoxic effect was tested by cellular morphology, 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐tetrazolium and flow cytometry assays. The expression of cellular membrane surface P‐gp was determined by flow cytometry. Results showed that the cellular heterogeneity exists in DOX uptake. The single‐high DOX schedule leads to lower uptake heterogeneity and higher mean drug uptake. The cellular heterogeneity in DOX uptake was found to be negatively correlated with drug cytotoxicity and surface P‐gp expression, with r = ?0.7680 to ~ ?0.9587. VER reduces the cellular variation in DOX uptake, suggesting that surface P‐gp may be one of the causes of the cellular heterogeneity in DOX uptake. This research demonstrates the importance of quantitative study of cellular heterogeneity in drug uptake and its potential application in drug schedule design, response prediction and therapy modulation. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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采用薄膜分散法合成磷脂微囊,根据胶粒的双电层理论,通过在微囊中加入氯化锰、氯化钙和氯化镁电解质溶液,使微囊处于相对稳定的状态.研究发现加入氯化锰和氯化钙溶液,微囊胶体的粒径没有明显的变化,但加入一定浓度氯化镁溶液,其粒径明显变大.为了进一步增加磷脂微囊稳定性,将氯化锰、氯化钙、氯化镁磷脂微囊胶体分别与海藻酸钠(SA)溶液混合.结果表明,氯化镁与SA几乎不能形成水凝胶,氯化钙与SA形成水凝胶能力强于氯化锰.微囊胶体溶液中的磷脂酰丝氨酸(PS)可以与Ca~(2+)和Mg~(2+)键合形成PS-Ca~(2+)和PS-Mg~(2+),但不能与Mn~(2+)键合形成PS-Mn~(2+).对氯化钙磷脂微囊与海藻酸钠合成的复合水凝胶的形貌、溶胀率及细胞毒性进行了表征,结果表明,氯化钙与SA形成的水凝胶可以捕获胶体中磷脂微囊,且形貌规整,结构稳定,无细胞毒性. 相似文献
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998.
Weichao Dong Dr. Yuchao Wang Yajing Zhang Dr. Xiangju Song Prof. Hui Peng Prof. Heqing Jiang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(69):17428-17436
Interfacial evaporation has emerged as a promising approach to produce freshwater. However, an urgent concern is that, due to the illegal discharge of industrial wastewater, most water bodies are polluted by trace volatile organic compounds (VOCs), which are easily volatilized and enriched in the collected water during the interfacial evaporation process. Herein, a bilayer photothermal evaporator was reasonably designed for contaminated water purification. The bottom hydrophilic rGO-sodium alginate (SA) sheets purposefully disintegrate water transport channels, thus quickly removing VOCs through physical adsorption. The rGO-SA-TiO2 upper layer sufficiently absorbs incident light and therefore persistently generates reactive oxidizing species to degrade upward VOCs. Notably, the oriented microchannels inside the evaporator allow sustained light reflections to improve the utilization of solar energy. The evaporation rate can reach 1.63 kg m−2 h−1 with a considerably high VOC removal efficiency of up to 96 %. Such an integrated bilayer evaporator provides an effective strategy to obtain clean water via solar distillation. 相似文献
999.
Shaoyong Ke Zhigang Zhang Ya-Ni Zhang Liqiao Shi Ronghua Zhou Aibing Jiang Ying Liang Ziwen Yang 《Research on Chemical Intermediates》2012,38(8):1827-1837
A novel series of ether functionalization of spiro-tetronic acid derivatives have been designed and conveniently synthesized via three steps, including esterification, one-pot heterocyclization, and etherification reactions. The target molecules have been identified on the basis of analytical spectra data. All newly synthesized compounds have been screened for their potential insecticidal activity against Heliothis armigera and Plutella xylostella compared with spirodiclofen by standard method. 相似文献
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