Abstract

IDENTIFICATION, ISOLATION AND CHARACTERIZATION OF DIMER IMPURITIES IN ANTIMUSCARINIC AGENT DARIFENACIN HYDROBROMIDE

P. Badarinadh Gupta*, B. Venkateswara Rao, S. Paul Douglas, Hemant Kumar Sharma and D. Vijaya Bharathi

Abstract

Darifenacin hydrobromide, antimuscarinic agent with actions similar to those of atropine and has greater selectivity for the muscarinic receptors of the urinary bladder, is used to treat symptoms of urge urinary incontinence, urgency, and frequency. It is an antagonist on the effects of muscarinic receptors in cholinergically mediated functions including stimulation of salivary secretion. The present study describes the identification, isolation and characterization of two process related dimer impurities in darifenacin hydrobromide using high performance liquid chromatography (HPLC) analysis. Impurities were identified using liquid chromatography coupled with time of flight mass spectrometry (LC-MS/TOF). Proposed structures were unambiguously confirmed by characterization using nuclear magnetic resonance spectroscopy (NMR), infrared spectroscopy (IR), mass spectroscopy and elemental analysis.

Keywords: Darifenacin, Isolation and Characterization of dimer impurities, NMR.