title: Structural studies of impurities of risperidone by hyphenated techniques.
abstract: During the impurity profile of risperidone (RSP), a more polar impurity (RSP-1) and a more non-polar impurity (RSP-2) were detected in LC-MS with respect to risperidone. These impurities were isolated, enriched and were subjected to mass and NMR spectral studies. Based on the spectral data, RSP-1 and RSP-2 were characterized as risperidone N-oxide and 9-methylene risperidone, respectively. The formation of these impurities is rationalized. The structures of both the impurities were unambiguously confirmed by single crystal XRD Studies.
authors.affiliation: Department of Analytical Research, Discovery Research, Dr. Reddy's Laboratories Ltd., Bollaram Road, Miyapur, Hyderabad 500 049, India.
authors.forename: P
authors.initials: P
authors.lastname: Sattanathan
authors.forename: J Moses
authors.initials: JM
authors.lastname: Babu
authors.forename: K
authors.initials: K
authors.lastname: Vyas
authors.forename: R B
authors.initials: RB
authors.lastname: Reddy
authors.forename: S T
authors.initials: ST
authors.lastname: Rajan
authors.forename: P
authors.initials: P
authors.lastname: Sudhakar
mesh_terms: D014150:Antipsychotic Agents / Q000032:analysis* / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D018360:Crystallography, X-Ray; D004340:Drug Contamination; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D018967:Risperidone / Q000031:analogs & derivatives* / Q000032:analysis* / Q000737:chemistry
chemical_list: D014150:Antipsychotic Agents; D007202:Indicators and Reagents; D018967:Risperidone