title: Structural studies of racecadotril and its process impurities by NMR and mass spectroscopy.
abstract: Three unknown impurities in racecadotril bulk drug at levels below 0.5% were detected by simple reverse phase isocratic high performance liquid chromatography (HPLC). Structures for these impurities were proposed by molecular ion information and their fragmentation pattern obtained by LC-MS and these impurities were confirmed by NMR spectroscopy. The impurities I, II and III were characterized as benzyl 2-methyl carboximido acetate, benzyl 2-phenyl ethyl carboximido acetate, and benzyl 2-(1-benzyl vinyl carboximido) acetate. These structures were further confirmed by co-injecting of synthetic standards of impurities with racecadotril. The mechanism of the formation of these process related impurities is discussed.
authors.affiliation: Department of Analytical Research, Discovery Research, Dr. Reddy's Laboratories Ltd., Miyapur, Hyderabad, India.
authors.forename: K Mallikarjun
authors.initials: KM
authors.lastname: Reddy
authors.forename: J Moses
authors.initials: JM
authors.lastname: Babu
authors.forename: P
authors.initials: P
authors.lastname: Sudhakar
authors.forename: M S P
authors.initials: MS
authors.lastname: Sharma
authors.forename: G Sudershan
authors.initials: GS
authors.lastname: Reddy
authors.forename: K
authors.initials: K
authors.lastname: Vyas
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004340:Drug Contamination; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D021241:Spectrometry, Mass, Electrospray Ionization; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D015244:Thiorphan / Q000031:analogs & derivatives* / Q000032:analysis
chemical_list: C049331:racecadotril; D015244:Thiorphan