Synthesis of 1-azido-2-(2’,4’,6’-trinitro phonyl) ethane,2,4.-bis( N-nitro )ethylamino-6-azido-1,3,5-triazine and tetraazido methylene methane, and the im proved preparation of 3-nitro-1,5-diazido-3-azapentane are discribed.Some properties of the four compounds are discussed as well.