Hypoxia, regions of low oxygen, occurs in a range of biological environments, and is involved in human diseases, most notably solid tumours. Exploiting the physiological differences arising from low oxygen conditions provides an opportunity for development of targeted therapies, through the use of bioreductive prodrugs, which are selectively activated in hypoxia. Herein, we describe an improved method for synthesising the most widely used bioreductive group, 2-nitroimidazole. The improved method is applied to an efficient synthesis of the anti-cancer drug Evofosfamide (TH-302), which is currently in Phase III clinical trials for treatment of a range of cancers.