1-(3-{2-[4-(2-Methyl-5-quinolinyl)-1-piperazinyl] ethyl} phenyl)-2-imidazolidinone, 1, was identified as a potential drug for the treatment of depression and anxiety. Herein is described the work carried out to select the manufacturing route and the process research studies to optimize the key stages of route B. A particular focus is given to the genotoxic impurities, related to this route, as one of the intermediates of the manufacturing route was genotoxic ...