Using 2, 3, 5, 6-tetraamineopyridine hydrochloride and triethoxy methane as starting materials, N-heterocyclic nitramine precursor 1, 5-2H-diimidazo [4, 5-b:4′, 5′-e] pyridine was prepared by condensation reactions. The optimum molar ratio of triethoxy methane/2, 3, 5, 6-tetraamineopyridine hydrochloride was indentified to be 4.5. The yield was 56.5%. 2, 9-Dialdehyde-5, 13-dithio-2, 4, 6, 7, 9, 11, 12, 14-octaaza-tricyclo[8.4.0.0^{3, 8}]tetradecane was synthesized using thiosemicarbazide and 1, 4-diformyl-2, 3, 5, 6-tetrahydroxylpiperazine as raw materials. The optimum molar ratio of thiosemicarbazide/1, 4-diformyl-2, 3, 5, 6-tetrahydroxylpiperazine was indentified to be 2.2. The yield was 46.0%. Their structures were characterized by ¹H NMR, IR, MS and elemental analyses. The geometry optimization and frequency vibration analysis of two N-heterocyclic nitramine precursors were performed by density functional theory DFT-B3LYP/6-311+G(d) method. Thermodynamic properties of two precursors in the temperature range of 200 K to 800 K were investigated. Results show that the constant pressure molar capacity, standard molar entropy and standard molar enthalpy of two N-heterocyclic nitramine precursors increase with the increase of temperature.