头孢菌素E-异构体杂质的核磁共振波谱特征研究

NMR Spectroscopic Characteristics of Cephalosporin E-isomer Impurities

目的阐述头孢菌素类抗生素E-异构体杂质的核磁共振波谱特征。方法应用^(1)H-NMR、^(13)C-NMR、DEPT技术以及二维核磁共振技术对头孢曲松、头孢噻肟、头孢吡肟及其E-异构体的质子信号和碳信号进行测试。结果在全归属6种头孢菌素的核磁信号基础上,对E-异构体的特征性质子和碳原子的化学位移进行了系统分析,总结了头孢菌素E-异构体的核磁共振波谱特征。结论与Z-型头孢菌素相比,头孢菌素E-异构体杂质7位侧链的^(1)H-NMR和^(13)C-NMR谱有明显特征,可用于头孢菌素Z,E-异构体的结构鉴别。

OBJECTIVE To summarize the NMR spectroscopic characteristics and regularities of cephalosporin E-isomer impurities.METHODS The 2D-NMR techniques of ^(1)H-^(1)H COSY,HMQC,HMBC were used to detect ceftriaxone,cefotaxime,cefepime and their E-isomers.RESULTS On the basis of the full assignments of the ^(1)H and ^(13)C spectra of six cephalosporins,systematic researches were carried out on the characteristic ^(1)H and ^(13)C signals.The spectroscopic regularities of cephalosporin E-isomers in NMR spectrum were summarized.CONCLUSION Compared with the Z-iomers of cephalosporins,the ^(1)H-NMR and ^(13)C-NMR spectra of the side chain at 7-position of cephalosporin E-isomer impurities have obvious characteristics,which can be used for chemical structure identification of cephalosporin E-isomer impurities.