Characterization of degradation products resulted from acidic hydrolysis of lisinopril under drastic conditions

Four degradation products resulted from acidic hydrolysis of lisinopril under drastic conditions. The degradation products were detected by means of ultra-performance liquid chromatography coupled with mass/mass spectroscopy (LC-MS/MS) with simple and sensitive method suitable for LC-MS/MS analysis. The fragmentation behaviors of lisinopril and degradation products were investigated. Two degradation products were described in E.Ph.(8th) as impurities. Both of 6-amino-2-((1-carboxy-3-phenylpropyl)amino) hexanoic acid (m/z 309+)and 1-(2,6-diaminohexanoyl)pyrrolidine-2-carboxylic acid (m/z 244+) were formed and identified.