以氨基甲磺酸为原料,经烷基化、环合、成盐等反应合成头孢尼西钠的重要中间体1-磺酸甲基四氮唑-5-硫醇双钠盐。将微波辐射技术应用到烷基化反应中,探讨了微波辐射功率、时间、溶剂对反应的影响,最佳反应条件为:以乙醇和水为溶剂,微波辐...以氨基甲磺酸为原料,经烷基化、环合、成盐等反应合成头孢尼西钠的重要中间体1-磺酸甲基四氮唑-5-硫醇双钠盐。将微波辐射技术应用到烷基化反应中,探讨了微波辐射功率、时间、溶剂对反应的影响,最佳反应条件为:以乙醇和水为溶剂,微波辐射功率250 W,辐射8min,磺甲基二硫代氨基甲酸乙酯钾盐的收率84.0%;用乙醇钠成盐,1-磺酸甲基四氮唑-5-硫醇双钠盐收率88.3%。产物总收率68.1%(以氨基甲磺酸计),纯度99.3%(HPLC),产物结构经IR、1 H NMR、MS和元素分析进行了确证。展开更多
Corrosion inhibition of mild steel in 1 mol/L HC1 by amoxicillin and ceftriaxone in the concentration range of 1.00×10^-5-1.00×10^-2 mol/L has been studied using weight loss, electrochemical potentiodynamic ...Corrosion inhibition of mild steel in 1 mol/L HC1 by amoxicillin and ceftriaxone in the concentration range of 1.00×10^-5-1.00×10^-2 mol/L has been studied using weight loss, electrochemical potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and quantum chemistry tests at 298 K. The weight loss experiment showed that the inhibition efficiency increased with amoxicillin and ceftriaxone concentrations to attain the maximums of 80.3% and 94.1%, respectively at 1.00×10^-2 mol/L. Potentiodynamic polarization indicated that amoxicillin and ceftriaxone acted as mixed-type inhibitors but mainly inhibited cathode hydrogen evolution reaction for mild steel in 1 mol/L HC1. The electrochemical impedance spectroscopy (EIS) demonstrated the inhibitors covered the active points of metal surface to inhibit corrosion. The absorption of both inhibitors on the mild steel surface was found to follow Langmuir adsorption isothermal and dominantly involve chemical adsorption at 298 K. Scanning electron microscopy (SEM) confirmed both of the inhibitors played a significant protective effect in mild steel corrosion in 1 mol/L HC1. The relationship between the inhibition properties and molecular structure had been discussed by quantum chemistry calculation. All the experimental results concluded that both amoxicillin and ceftriaxone acted as good corrosion inhibitors and their inhibition efficiency was in the order of ceftriaxone 〉 amoxicillin.展开更多
文摘以氨基甲磺酸为原料,经烷基化、环合、成盐等反应合成头孢尼西钠的重要中间体1-磺酸甲基四氮唑-5-硫醇双钠盐。将微波辐射技术应用到烷基化反应中,探讨了微波辐射功率、时间、溶剂对反应的影响,最佳反应条件为:以乙醇和水为溶剂,微波辐射功率250 W,辐射8min,磺甲基二硫代氨基甲酸乙酯钾盐的收率84.0%;用乙醇钠成盐,1-磺酸甲基四氮唑-5-硫醇双钠盐收率88.3%。产物总收率68.1%(以氨基甲磺酸计),纯度99.3%(HPLC),产物结构经IR、1 H NMR、MS和元素分析进行了确证。
基金supported by China Postdoctoral Science Fundation(201003655 & 20080461269)the Postdoctoral Independent Innovation Fund of Shandong Province(200902040)+1 种基金the project of Sichuan Ministry of Education(2010CL06)the Open Fund of Ocean Corrosion and Protection Research and Development Center,Institute of Oceanology, Chinese Academy of Sciences(200901005)
文摘Corrosion inhibition of mild steel in 1 mol/L HC1 by amoxicillin and ceftriaxone in the concentration range of 1.00×10^-5-1.00×10^-2 mol/L has been studied using weight loss, electrochemical potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and quantum chemistry tests at 298 K. The weight loss experiment showed that the inhibition efficiency increased with amoxicillin and ceftriaxone concentrations to attain the maximums of 80.3% and 94.1%, respectively at 1.00×10^-2 mol/L. Potentiodynamic polarization indicated that amoxicillin and ceftriaxone acted as mixed-type inhibitors but mainly inhibited cathode hydrogen evolution reaction for mild steel in 1 mol/L HC1. The electrochemical impedance spectroscopy (EIS) demonstrated the inhibitors covered the active points of metal surface to inhibit corrosion. The absorption of both inhibitors on the mild steel surface was found to follow Langmuir adsorption isothermal and dominantly involve chemical adsorption at 298 K. Scanning electron microscopy (SEM) confirmed both of the inhibitors played a significant protective effect in mild steel corrosion in 1 mol/L HC1. The relationship between the inhibition properties and molecular structure had been discussed by quantum chemistry calculation. All the experimental results concluded that both amoxicillin and ceftriaxone acted as good corrosion inhibitors and their inhibition efficiency was in the order of ceftriaxone 〉 amoxicillin.