Abstract

Spectral characterization of itraconazole impurities in the drug product

Author(s): Nirmala Munigela, J.Moses Babu, Anjaneyulu Yerramilli, Sudhakar Parthasarathy, Vyas Krishnamurthy, K.N.Reddy

Two unknown impurities, Impurity-1 and Impurity-2 in itraconazole drug product were detected using a simple isocratic reversed-phase high performance liquid chromatography (HPLC or LC). These impurities were enriched by heat stress of the drug product and isolated from degraded sample by column purification followed by isolation through preparative high performance liquid chromatography (Prep HPLC). Based on the 2 dimensional -nuclear magnetic resonance spectroscopy (2D-NMR) data and mass spectral (MS) the Impurity-1 and 2 were characterized as N-[4- (1-sec-Butyl-5-oxo-1, 5-dihydro-[1,2,4]triazol-4-yl)-phenyl]-N-[2-({4-[2-(2,4- dichloro-phenyl)-2-[1,2,4]triazol-1-yl-methyl [1,3] dioxolan-4-ylmethoxy]- phenyl}-formyl-amino)-ethyl formamide andN-{2-[4-(1-sec-Butyl-5-oxo- 1,5-dihydro-[1,2,4]triazol-4-yl)-phenyl amino]-ethyl}-N-{4-[2-(2,4- dichlorophenyl)-2-[1,2,4]triazol-1-yl-methyl-[1,3]dioxolan-4-ylmethoxy]- phenyl}-formamide respectively. The formation of these impurities is explained.