title: Detection, isolation and characterization of principal synthetic route indicative impurities in verapamil hydrochloride.
abstract: Two unknown impurities were detected in verapamil hydrochloride bulk drug using isocratic reversed-phase high performance liquid chromatography (HPLC). These impurities were isolated by preparative HPLC. Spectral data for the isolated impurities were collected. Based on the spectral data derived from two-dimensional nuclear magnetic resonance (2D-NMR) spectroscopy and mass spectrometry (MS), impurity-1 and impurity-2 were characterized as 2-(3,4-dimethoxyphenyl)-3-methylbut-2-enenitrile and 2-(3,4-dimethoxyphenyl)-2-isopropyl-3-methylbutanenitrile, respectively.
authors: Analytical Development Laboratory, Piramal Healthcare Ltd, Ennore, Chennai 600 057, India.
authors: Viswanathan
authors: V
authors: Srinivasan
authors: Hariharan
authors: H
authors: Sivaramakrishnan
authors: Balakrishnan
authors: B
authors: Karthikeyan