Alternative synthesis of the anti-baldness compound RU58841

Abstract

RU58841 is active against baldness and is commercially available. The previously reported synthesis uses phosgene, three discrete inert atmosphere steps and three steps that require flash chromatography. Our synthesis uses no phosgene, only one inert atmosphere step and does not require flash chromatography. This is achieved by stepwise construction of the hydantoin moiety around the amino group of 3-trifluoromethyl-4-cyanoaniline and ring closure to give a 2-nitropropane leaving group. On a small scale we achieved an overall yield of 33%.