title: Impurity profile study of repaglinide.
abstract: Three unknown impurities and a byproduct in repaglinide bulk drug at levels below 0.1% (ranging from 0.05 to 0.1%) were detected by a simple isocratic reversed-phase high performance liquid chromatography (HPLC) method. These impurities were isolated from crude sample of repaglinide using reversed-phase preparative high performance liquid chromatography. Based on the spectroscopic data (IR, NMR and MS) the structures of these impurities (I, II and IV) and byproduct (III) were characterised as 4-carboxymethyl-2-ethoxy-benzoic acid (I), 4-cyclohexylaminocarbamoylmethyl-2-ethoxy-benzoic acid (II), 1-cyclohexyl-3-[3-methyl-1-(2-piperidin-1-yl-phenyl)-butyl]-urea (IV) and 1,3-dicyclohexyl urea (III), respectively. Their synthesis and formation is discussed.
authors.affiliation: Department of Analytical Research, Discover Research, Dr. Reddy's Laboratories Ltd., Bollaram Road, Miyapur, Hyderabad 500 050, India.
authors.forename: K V S R Krishna
authors.initials: KV
authors.lastname: Reddy
authors.forename: J Moses
authors.initials: JM
authors.lastname: Babu
authors.forename: Vijayavitthal T
authors.initials: VT
authors.lastname: Mathad
authors.forename: S
authors.initials: S
authors.lastname: Eswaraiah
authors.forename: M Satyanarayana
authors.initials: MS
authors.lastname: Reddy
authors.forename: P K
authors.initials: PK
authors.lastname: Dubey
authors.forename: K
authors.initials: K
authors.lastname: Vyas
mesh_terms: D002219:Carbamates / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D004340:Drug Contamination; D007004:Hypoglycemic Agents / Q000032:analysis*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D010880:Piperidines / Q000032:analysis*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D002219:Carbamates; D007004:Hypoglycemic Agents; D010880:Piperidines; C072379:repaglinide