Characterization of the trace-level impurities in the bulk drug citalopram by high-performance liquid chromatography/tandem multistage mass spectrometry.
Five trace impurities were detected in the bulk drug citalopram using high-performance liquid chromatography with UV detection. A simple and sensitive method suitable for liquid chromatography tandem multistage mass spectrometry (HPLC/MS(n)) analysis was developed. Using this method, the fragmentation behavior of citalopram and the impurities was investigated. Four impurities were rapidly characterized, and an unknown impurity was elucidated as 3-(3-dimethylaminopropyl)-N-(1-(3-dimethylaminopropyl)-1-(4-fluorophenyl)-1,3-dihydroisobenzofuran-5-yl)-3-(4-fluorophenyl)-1,3-dihydroisobenzofuran-5-carboxamide on the basis of the MS(n) and exact mass evidence, and the proposed structure was further confirmed by nuclear magnetic resonance (NMR) experiments after preparative isolation.
Sun
Cuirong
C
Department of Polymer Science & Engineering, Zhejiang University, Hangzhou 310027, China.
Xu
Hui
H
Pan
Yuanjiang
Y
Shen
Zhiquan
Z
Wang
Danhua
D
D018687:Antidepressive Agents, Second-Generation / Q000032:analysis / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D015283:Citalopram / Q000032:analysis* / Q000737:chemistry*; D004340:Drug Contamination / Q000517:prevention & control*; D004353:Drug Evaluation, Preclinical / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*
D018687:Antidepressive Agents, Second-Generation; D015283:Citalopram