2-硝基咪唑是一种重要的医药中间体,可用于合成多种抗癌药物,通过对其结构进行修饰,有望开发新型活性药物分子。以2-氨基嘧啶和3-溴丙酮酸乙酯为起始原料,经过缩合环化、肼解、氧化和取代合成了一系列1-烷基-2-硝基-1 H-咪唑-5-甲酸乙酯...2-硝基咪唑是一种重要的医药中间体,可用于合成多种抗癌药物,通过对其结构进行修饰,有望开发新型活性药物分子。以2-氨基嘧啶和3-溴丙酮酸乙酯为起始原料,经过缩合环化、肼解、氧化和取代合成了一系列1-烷基-2-硝基-1 H-咪唑-5-甲酸乙酯(7a~7d)及其同分异构体1-烷基-2-硝基-1 H-咪唑-4-甲酸乙酯(8a~8d),该方法克服了传统合成路线中氮原子上取代基仅为甲基的局限性。研究不同取代基对2种异构体比例的影响,结果表明:随着取代基团的给电子能力增强,更加有利于化合物7的生成。所有合成化合物的结构都经过1 H NMR,13 C NMR和MS(ESI)确证或表征。展开更多
Government investment plays an important role in promoting and guiding the economic and social development in China.Xinjiang is the core province of the Belt and Road and its economic growth is mainly driven by invest...Government investment plays an important role in promoting and guiding the economic and social development in China.Xinjiang is the core province of the Belt and Road and its economic growth is mainly driven by investment.This paper decomposes the determinants of government investment effect into economic structure change,technological change and investment structure change,using the non-competitive input-output table of Xinjiang province in 2007,2012 and 2015 and structural decomposition analyses.The results show that,the government investment effect in Xinjiang shows a slight decline trend.During the period,the change of economic structure and investment structure have the negative impact on government investment effect,while the change of technology has the positive impact on government investment effect.In addition,these impacts have strong sectoral heterogeneity.展开更多
文摘2-硝基咪唑是一种重要的医药中间体,可用于合成多种抗癌药物,通过对其结构进行修饰,有望开发新型活性药物分子。以2-氨基嘧啶和3-溴丙酮酸乙酯为起始原料,经过缩合环化、肼解、氧化和取代合成了一系列1-烷基-2-硝基-1 H-咪唑-5-甲酸乙酯(7a~7d)及其同分异构体1-烷基-2-硝基-1 H-咪唑-4-甲酸乙酯(8a~8d),该方法克服了传统合成路线中氮原子上取代基仅为甲基的局限性。研究不同取代基对2种异构体比例的影响,结果表明:随着取代基团的给电子能力增强,更加有利于化合物7的生成。所有合成化合物的结构都经过1 H NMR,13 C NMR和MS(ESI)确证或表征。
基金Supported by the National Natural Science Foundation of China(71988101,71673269)
文摘Government investment plays an important role in promoting and guiding the economic and social development in China.Xinjiang is the core province of the Belt and Road and its economic growth is mainly driven by investment.This paper decomposes the determinants of government investment effect into economic structure change,technological change and investment structure change,using the non-competitive input-output table of Xinjiang province in 2007,2012 and 2015 and structural decomposition analyses.The results show that,the government investment effect in Xinjiang shows a slight decline trend.During the period,the change of economic structure and investment structure have the negative impact on government investment effect,while the change of technology has the positive impact on government investment effect.In addition,these impacts have strong sectoral heterogeneity.