Isolation, synthesis and structure confirmation of the impurity in crude roflumilast product
作者:Yan Lin、Peijun Huang、Haofei Qi、Ligong Chen、Donghua Wang
DOI:10.1007/s11164-012-0823-3
日期:2013.9
An impurity was isolated from crude synthesized roflumilast and characterized by 1H NMR, 13C NMR, and HR-MS, which confirmed the structure as N-(3,5-dichloropyrid-4-yl)-4-difluoromethoxy-3-hydroxybenzamide. To further verify the structure, this compound was synthesized from 4-difluoromethoxy-3-hydroxybenzaldehyde. Comparison of the 1H NMR, 13C NMR, HR-MS, and the HPLC spectrum of the impurity and the
从合成的粗鲁氟司特中分离出杂质,并通过1 H NMR,13 C NMR和HR-MS进行表征,证实其结构为N-(3,5-二氯吡啶-4-基)-4-二氟甲氧基-3-羟基苯甲酰胺。为了进一步验证结构,该化合物由4-二氟甲氧基-3-羟基苯甲醛合成。杂质和真实样品的1 H NMR,13 C NMR,HR-MS和HPLC光谱比较表明,该杂质为N-(3,5-二氯吡啶-4-基)-4-二氟甲氧基-3 -羟基苯甲酰胺。这证明了监测罗氟司特反应过程的重要性。