کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1221162 | 967815 | 2011 | 8 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Investigation and structural elucidation of a process related impurity in candesartan cilexetil by LC/ESI-ITMS and NMR Investigation and structural elucidation of a process related impurity in candesartan cilexetil by LC/ESI-ITMS and NMR](/preview/png/1221162.png)
Four impurities were detected in candesartan cilexetil bulk drug samples by HPLC and LC/MS. These impurities were marked as CDC-I, II, III and IV. One of the impurities CDC-II was unknown and has not been reported previously. An optimized method using liquid chromatography coupled with electrospray ionization ion trap mass spectrometry (LC/ESI-ITMS) in positive ion mode has been developed to carry out structural identification of unknown impurity. Based on mass spectrometric data and synthetic specifics the structure of CDC-II was proposed as 2-ethoxy-1-[[2′-(1-ethyl-1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-1H-benzimidazole-7-carboxylic acid ethyl ester. The impurity was isolated by semi-preparative HPLC and structure was confirmed by NMR spectroscopy. The plausible mechanism for the formation of impurities is also discussed.
Journal: Journal of Pharmaceutical and Biomedical Analysis - Volume 56, Issue 2, 10 September 2011, Pages 256–263