title: Structural characterization of impurities in pioglitazone.
abstract: In the pioglitazone bulk drug three prominent impurities I-III were detected up to concentrations of 0.1% (ranging from 0.05-0.1%) by reversed phase HPLC. These impurities were isolated from enriched mother liquor samples and characterized as 5-(4-hydroxybenzyl)-1,3-thiazolidine-2,4-dione (I) 5-(4-fluorobenzyl)-1,3-thiazolidine-2,4-dione (II), 2-[2-(4-bromophenoxy) ethyl-5-ethyl pyridine (III) based on their 1H, and 13C NMR, DEPT, Mass and IR spectral data. Structure elucidation and synthesis of these impurities is discussed.
authors.affiliation: Dr. Reddy's Laboratories Ltd., Hyderabad, India.
authors.forename: Y R
authors.initials: YR
authors.lastname: Kumar
authors.forename: A R
authors.initials: AR
authors.lastname: Reddy
authors.forename: S
authors.initials: S
authors.lastname: Eswaraiah
authors.forename: K
authors.initials: K
authors.lastname: Mukkanti
authors.forename: M S N
authors.initials: MS
authors.lastname: Reddy
authors.forename: M V
authors.initials: MV
authors.lastname: Suryanarayana
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004340:Drug Contamination; D007004:Hypoglycemic Agents / Q000138:chemical synthesis / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D000077205:Pioglitazone; D013055:Spectrophotometry, Infrared; D017550:Spectroscopy, Fourier Transform Infrared; D045162:Thiazolidinediones / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D007004:Hypoglycemic Agents; D045162:Thiazolidinediones; D000077205:Pioglitazone