Structural characterization of impurities in pioglitazone.
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.
Kumar
Y R
YR
Dr. Reddy's Laboratories Ltd., Hyderabad, India.
Reddy
A R
AR
Eswaraiah
S
S
Mukkanti
K
K
Reddy
M S N
MS
Suryanarayana
M V
MV
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*
D007004:Hypoglycemic Agents; D045162:Thiazolidinediones; D000077205:Pioglitazone