Three impurities ranging from 0.08%-0.12% by peak area in anastrozole active pharmaceutical ingredient were detected by simple isocratic reverse-phase high performance liquid chromatography (HPLC). These impurities were isolated by prep-HPLC and were characterized by LC-MS/MS, GCMS and NMR experimental data. Based on the results obtained from different spectroscopic experiments, these impurities have been characterized as 2,2’-(5-((4H-1,2,4-triazol-4-yl)methyl)-1,3-phenylene)bis(2-methylpropanenitrile) (Impurity I), 2,2’-(5-methyl-1,3-phenylene)bis(2-methylpropanenitrile) (Impurity II) and 2,2’-(5-(bromomethyl)-1,3-phenylene)bis(2-methyl-propanenitrile) (Impurity III).
anastrozole; prep-HPLC; impurities; Mass Spectrometry; NMR; identification and characterization
