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Gan Zhou Shuyun Shi Wei Zhang Zhirong Tan Yao Chen Dong Guo Honghao Zhou Haitang Hu Jin Tan 《Biomedical chromatography : BMC》2010,24(10):1130-1135
Ilaprazole is a new proton pump inhibitor designed for the treatment of gastric ulcers, and limited data is available on the metabolism of the drug. In this article, the structural elucidation of urinary metabolites of ilaprazole in human was described by HPLC‐ESI‐MS/MS and stopped‐flow HPLC‐NMR experiments. Urinary samples were precipitated by sodium carbonate solution, and then extracted by liquid–liquid extraction after adding ammonium acetate buffer solution. The enriched sample was separated using a C18 reversed‐phase column with the mobile phase composed of acetonitrile and 0.05 mol/L ammonium acetate buffer solution in a gradient solution, and then directly coupled to ESI‐MS/MS detection in an on‐line mode or 1H‐NMR (500 MHz) spectroscopic detection in a stopped‐flow mode. As a result, four sulfide metabolites, ilaprazole sulfide (M1), 12‐hydroxy‐ilaprazole sulfide (M2), 11,12‐dihydroxy‐ilaprazole sulfide (M3) and ilaprazole sulfide A (M4), were identified by comparing their MS/MS and NMR data with those of the parent drug and available standard compounds. The main biotransformation reactions of ilaprazole were reduction and the aromatic hydroxylation of the parent drug and its relative metabolites. The result testified that HPLC‐ESI‐MS/MS and HPLC‐NMR could be widely applied in detection and identification of novel metabolites. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Iron(II)‐Catalyzed Site‐Selective Functionalization of Unactivated C(sp3)−H Bonds Guided by Alkoxyl Radicals 下载免费PDF全文
Honghao Guan Shutao Sun Ying Mao Lei Chen Ran Lu Jiancheng Huang Prof. Dr. Lei Liu 《Angewandte Chemie (International ed. in English)》2018,57(35):11413-11417
An alkoxyl radical guided strategy for site‐selective functionalization of unactivated methylene and methine C?H bonds enabled by an FeII‐catalyzed redox process is described. The mild, expeditious, and modular protocol allows efficient remote aliphatic fluorination, chlorination, amination, and alkynylation of structurally and electronically varied primary, secondary, and tertiary hydroperoxides with excellent functional‐group tolerance. The application for one‐pot 1,4‐hydroxyl functionalization of non‐oxygenated alkane substrates initiated by aerobic C?H oxygenation is also demonstrated. 相似文献
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A method for rapid preparative isolation and screening of antioxidants has been developed by combining preparative HSCCC with on-line radical scavenging detection by use of DPPH· (1,1-diphenyl-2-picrylhydrazyl) as model radical. The HSCCC effluent was split into two parts. The major part was collected and the rest was introduced, through a switch valve, directly into a reaction coil for on-line evaluation of antioxidant activity. Each of the antioxidants separated by HSCCC reacted postcolumn with the DPPH· solution in methanol and was observed as a negative peak at 517 nm of size corresponding to its antioxidant activity. The on-line method was successfully used for preparative isolation and screening of antioxidant components from an ethyl acetate extract of the traditional Chinese medicine Selaginella moellendorffii. A total of 114.7 mg amentoflavone, 12.4 mg hinokiflavone, 7.2 mg podocarpusflavone A, and 1.1 mg ginkgetin, identified as the main radical scavengers, were obtained with purity of 99.4, 98.6, 98.9, and 99.2%, respectively, as determined by LC, from 1.0 g ethyl acetate extract. Their chemical structures were identified by MS and by UV and NMR spectroscopy. 相似文献
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Kristoffer Almdal Honghao Sun Allan K. Poulsen Lise Arleth Iver Jakobsen Hong Gu Anne Marie Scharff‐Poulsen 《先进技术聚合物》2007,18(12):1020-1020
In the article above published in Volume 17 of Polymers for Advanced Technologies, pages 790–793 (2006) and online in Wiley InterScience , ( www.wileyinterscience.wiley.com ) DOI 10.1002/pat.786 the following changes should be recognised: On the second page of the paper, page 791, the sentence above figure 2 should have read ‘Since the headgroup areas of surfactants are a weak function of the condition under which they are used the function …’ 相似文献
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采用爆轰合成的方法,以Ce(NO3)3·6H2O为原料,制得了CeO2纳米粒子. 炸药采用黑索金粉,添加剂为CO(NH2)2,NaNO2. 爆轰产物经水洗,烘干后,利用X射线衍射仪器和高分辨率透射电镜对实验结果进行了分析. XRD结果表明,该法所得到的CeO2为立方晶系,颗粒平均粒度为33 nm. TEM图像显示其颗粒呈球形,颗粒大小主要分布在20~40 nm之间,颗粒具有较好的分散性. 球形纳米CeO2颗粒的形成原因有两点:(1) 由于爆轰过程的快速性和急剧冷却的特点,CeO2晶粒来不及择优生长; (2) 产物Na2CO3的熔点较低,爆轰时呈熔融状态包覆在CeO2晶核的周围,阻隔了CeO2晶粒的团聚生长. 相似文献
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爆轰波碰撞的聚能效应 总被引:1,自引:0,他引:1
利用两高爆速导爆索对称布置于药卷两侧,起爆后炸药爆轰波在对称线处汇聚碰撞,当碰撞角度达到一定值时,发生马赫反射,使爆轰压力成倍增加,形成高压、高能量密度区域的聚能效应。本文在爆轰波传播碰撞理论的基础上,通过炸药做功能力和猛度试验验证爆轰波碰撞的聚能效果。做功能力试验结果表明爆轰波碰撞能够增加炸药能量利用率;猛度试验结果表明采用对称起爆技术下的爆轰波碰撞能够改变爆轰波在特定方向上的扩散作用。试验结果与爆轰波入射角的几何关系表明,当高爆速起爆药条与主装药爆速比例在1.15倍以上时,爆轰波碰撞能够达到一定的聚能效果。 相似文献
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Conventional optical nanoparticle pH sensors that are designed for ratiometric measurements in cells have been based on utilizing one sensor fluorophore and one reference fluorophore in each nanoparticle, which results in a relatively narrow dynamic measurement range. This results in substantial challenges when conducting live cell measurements, which often leads to misleading results. In the present work we provide a simple solution to this problem. 相似文献
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