In the title compound, C(9)H(15)N(3)O(4), the 1,3-dioxane ring displays a chair conformation and the five-membered ring is close to planar (r.m.s. deviation = 0.054 Å). An intra-molecular N-H⋯O hydrogen bond to one of the nitro-group O atoms generates an S(6) ring. In the crystal, inter-molecular N-H⋯O hydrogen bonds link the mol-ecules into C(6) chains propagating in [010] and a C-H⋯O link also occurs.