Preparation of 1-hydroxyethyl-2-trideuteriomethyl-5-nitroimidazole

The title compound was prepared by two different procedures. The first route starts with acetonitrile-d₃ and goes through 2-trideuteriomethyl-5-nitroimidazole ( 6 ) (Scheme I). The second and more convenient process is direct labeling of metronidazole ( 1 ) with alkaline ethanol-d₁.