Dual-function radiosensitizers. Alpha-[[(2-bromoethyl)amino]methyl]-2-nitro-1H-imidazole-1-ethanol and related compounds: preparation via an aziridine equivalent.

An improved synthesis of the dual-function radiosensitizer alpha-[[(2-bromoethyl)amino]methyl]-2-nitro-1H-imidazole-1-ethanol (2, RB 6145) has been developed. Previously, the synthetic difficulties associated with this compound limited its attractiveness as a clinical candidate, although its radiosensitizing activity in preclinical models warranted its further development. The synthesis described uses a 2-oxazolidinone as an aziridine equivalent and provides 2 in 47% yield.