1，3，5，5-Tetranitro-hexahydropyrimidine （DNNC） and 1，4，6，6-tetranitro-1，4-diazepane （TNDA） were synthesized from the reaction of 2，2-dinitropropane-1，3-diol with tert-butylamine and ethylenediamine， respectively. Their structures were characterized by nuclear magnetic resonance （NMR）， fourier infrared spectroscopy（FT-IR）， and single crystal X-ray diffraction. Meanwhile， their thermal behaviors and mechanical sensitivities were determined by differential scanning calorimetry-thermogravimetry（DSC-TG） and the BAM methods. Furthermore， isodesmic reactions and EXPLO5 were used to predict detonation parameters. The crystal structures indicate that the cyclohexane skeleton in DNNC and the cycloheptane skeleton in TNDA are both chair conformations. Both of them have extensive intermolecular and intramolecular non-classical hydrogen bonds. The results of DSC-TG show that the phase transition temperatures of DNNC and TNDA are 155.0 ℃ and 154.5 ℃， respectively. Furthermore， their peak decomposition temperatures are 215.3 ℃ and 205.9 ℃. In addition， DNNC and TNDA possess good mechanical sensitivity. Their impact sensitivities are 25 J and 17.5 J， and friction sensitivities are 144 N and 240 N. Besides， their theoretical detonation velocities are 8772 m·s^-1 and 7828 m·s^-1， and detonation pressures are 34.8 GPa and 25.0 GPa.