In the title compound, C(8)H(12)N(6)O(2), the molecular dimensions provide evidence for significant polarization of the electronic structure. There is an intramolecular N-H...N hydrogen bond, and the molecules are linked into complex sheets by a combination of two-centre hydrogen bonds, one each of the N-H...N and N-H...O types, and a three-centre N-H...(N,O) hydrogen bond.