1-(2′,2′,2′-trinitroethyl)-3,3-dinitroazetidine, 1,3-bi(3′,3′-dinitroazetidine)-2,,2-dinitropropane and 1-(3′,3′-dinitroazetidine)-2,2-dinitropropane were synthesized by Mannich reaction of 3,3-dinitroazetidine. Their molecular structures have been determined by elemental analysis, IR and ¹H NMR spectra.