The synthesis of the first examples of the 4-imidazo [4, 5-] isoxazole ring system are reported. These compounds are obtained in good yield by thermolysis of 2-(4-nitro-1- imidazol-5-yl) acetate and malonate derivatives, in turn readily available from reaction of 5- chloro-4-nitro-1-imidazoles with active methylene comp
