In the title molecule, C(9)H(7)N(5)O(3)S, there is an intramolecular N-H⋯O. The molecule is essentially planar, with the maximum deviation from the mean plane of the 18 non-H atoms being 0.135 (2) Å for the amine N atom. In the crystal, the molecules are connected via intermolecular N-H⋯O and N-H⋯S hydrogen bonds, forming two-dimensional networks lying parallel to (10[Formula: see text]). They are separated by an interplanar distance of 3.3214 (9) Å, leading to π-π interactions which stabilize the crystal structure.