Diammonium 1,1',3,3'-tetra-methyl-2,2',4,4',6,6'-hexa-oxoperhydro-5,5'-bipyrimidine-5,5'-diide monohydrate

In the title hydrated salt, 2NH(4) (+)·C(12)H(12)N(4)O(6) (2-)·H(2)O, the two hexa-hydro-pyrimidine rings in the dianion are inclined to one another at a dihedral angle of 62.76 (5)°. In the crystal structure, the anions and water mol-ecules are linked into sheets parallel to the bc plane by inter-molecular O-H⋯O hydrogen bonds and sustained by C-H⋯O contacts. The linking of the anions and water mol-ecules with the cations by N-H⋯O hydrogen bonds creates a three-dimensional extended network. The crystal structure is further stabilized by very weak C-H⋯π inter-actions.