Development of an Economical, Single Step Synthesis of FAZA, a Clinical Hypoxia Marker, and Potential Synthons to Prepare its Positional Analogs

F-18 analog of 1-α-D-(5'-deoxy-5'-fluoro-(1S,2R,3S,4S) arabinofuranosyl)-2-nitroimidazole (FAZA) is a clinical PET tracer for diagnosing hypoxic tumors in cancer patients. Original synthesis of FAZA is lengthy, expensive and low yielding (∼12%). Current procedure is fast, economical, and affords FAZA (25%) in a single step, along with three useful synthons, 3, 4 and 5, to prepare other positional analogues of FAZA. Their chemical ratio depends on the solvent and reaction conditions.