Impurities in Finasteride: Identification, Synthesis, Characterization and Control of Potential Carry-Over Impurities from Reagents Used for the Process

Abstract

An assessment of the impurity profile of finasteride and possible carry-over related substances likely to arise during the synthesis of finasteride is described in this article. Impurities in reaction mass were monitored by HPLC, potential impurities isolated with preparative HPLC and structures were substantiated by 1 H NMR, MS and MS-MS. Impurities RRT's were established by HPLC co-injection. Based on the spectral data structure of impurity I and impurity II were characterized as cyclohexyl and phenyl analog of finasteride.