2,6-Diamino-4-oxo-3,4-dihydropyrim-idin-1-ium chloride dihydrate

In the crystal structure of the title compound, C(4)H(7)N(4)O(+)·Cl(-)·2H(2)O, adjacent cations are connected to one another through N-H⋯O hydrogen bonds, forming infinite chains along the b axis. These chains are further hydrogen bonded to the chloride anions and water mol-ecules, resulting in a three-dimensional network. The pyrimidine rings of adjacent mol-ecules are arranged in an anti-parallel manner above each other with centroid-centroid distances of 3.435 (1) Å, indicative of π-π inter-actions.