Abstract Manganese dioxide oxidation of 2-hydroxymethyl-1-methyl-5-nitroimidazole (6) gave 1-methyl-5-nitroimidazole-2-carboxaldehyde (7) in high yield. Reaction of diazomethane with 7 afforded the title compound 1 in low yield. Treatment of ethyl acid malonate with two equivalents of isopropylmagnesium bromide in THF and subsequent addition to 1-methyl-5-nitroimidazole-2-carbonylimidazolide (12) yielded ethyl (1-methyl-5 ...