title: Identification, isolation and characterization of process-related impurities in Rizatriptan benzoate.
abstract: Three process-related impurities were observed in routine monitoring of the samples by HPLC. These impurities were identified by LC-MS. One of the impurities, Imp-3 [rizatriptan-2,5-dimer] was reported in literature. Other two impurities were isolated by preparative HPLC and characterized by NMR, Mass and IR. Pure impurities obtained by isolation were co-injected with Rizatriptan benzoate sample to confirm the retention times in HPLC. Structure elucidation of these impurities by spectral data has been discussed in detail. These impurities were identified as 4-(5-((1H-1,2,4-triazol-1-yl)methyl)-3-(2-(dimethylamino)ethyl)-1H-indol-1-yl)-4-(5-((1H-1,2,4-triazol-1-yl)methyl)-3-(2-(dimethylamino)ethyl)-1H-indol-2-yl)-N,N-dimethylbutan-1-amine [rizatriptan-1,2-dimer] and [4,4-bis-(5-((1H-1,2,4-triazol-1-yl)methyl)-3-(2-(dimethylamino)-ethyl)-1H-indol-2-yl)-N,N-dimethylbutan-1-amine [rizatriptan-2,2-dimer].
authors.affiliation: APL Research Centre (A Division of Aurobindo Pharma Ltd.), 313, Bachupally, Quthubullapur, Hyderabad-500072, India.
authors.forename: T Joseph Sunder
authors.initials: TJ
authors.lastname: Raj
authors.forename: Ch
authors.initials: Ch
authors.lastname: Bharathi
authors.forename: M Saravana
authors.initials: MS
authors.lastname: Kumar
authors.forename: Joseph
authors.initials: J
authors.lastname: Prabahar
authors.forename: P Naveen
authors.initials: PN
authors.lastname: Kumar
authors.forename: Hemant Kumar
authors.initials: HK
authors.lastname: Sharma
authors.forename: Kalpesh
authors.initials: K
authors.lastname: Parikh
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004340:Drug Contamination; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D013058:Mass Spectrometry / Q000379:methods; D015394:Molecular Structure; D015203:Reproducibility of Results; D017366:Serotonin Receptor Agonists / Q000032:analysis / Q000737:chemistry* / Q000592:standards; D013055:Spectrophotometry, Infrared / Q000379:methods; D014230:Triazoles / Q000032:analysis / Q000737:chemistry* / Q000592:standards; D014363:Tryptamines / Q000032:analysis / Q000737:chemistry* / Q000592:standards
chemical_list: D017366:Serotonin Receptor Agonists; D014230:Triazoles; D014363:Tryptamines; C093622:rizatriptan