title: Characterization of a novel trace-level impurity in lisinopril using multi-stage mass spectrometry.
abstract: An impurity in the bulk drug lisinopril was detected by simple reversed-phase high-performance liquid chromatography (HPLC). This trace-level impurity was rapidly identified as 2-(2-oxo-azocan-3-ylamino)-4-phenyl- butyric acid on the basis of the on-line multi-stage mass spectrometric evidence, and the proposed structure was further confirmed by multi-stage mass spectrometry of lisinopril and three related compounds.
authors.affiliation: Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang Province 310027, China.
authors.forename: Saifeng
authors.initials: S
authors.lastname: Pei
authors.forename: Danhua
authors.initials: D
authors.lastname: Wang
authors.forename: Cuirong
authors.initials: C
authors.lastname: Sun
authors.forename: Yuanjiang
authors.initials: Y
authors.lastname: Pan
mesh_terms: D001381:Azepines / Q000138:chemical synthesis / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid; D017706:Lisinopril / Q000592:standards*; D013058:Mass Spectrometry / Q000379:methods*; D010654:Phenylbutyrates / Q000138:chemical synthesis / Q000302:isolation & purification*; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: C521581:2-(2-oxoazocan-3-ylamino)-4-phenylbutyric acid; D001381:Azepines; D010654:Phenylbutyrates; D017706:Lisinopril