1,4-Bis(4,5-dihydro-1H-imidazol-2-yl)benzene-4-amino-benzene-sulfonic acid-water (1/2/2).

The asymmetric unit of the title compound, C(12)H(14)N(4)·2C(6)H(7)NO(3)S·2H(2)O, contains one half of a centrosymmetric 1,4-bis-(4,5-dihydro-1H-imidazol-2-yl)benzene (bib) molecule, one 4-amino-benzene-sulfonic acid molecule and one water mol-ecule. In the bib molecule, the imidazole ring adopts an envelope conformation. The benzene rings of bib and 4-aminobenzenesulfonic acid are oriented at a dihedral angle of 21.89 (4)°. In the crystal structure, inter-molecular N-H⋯O, O-H⋯N and O-H⋯O inter-actions link the mol-ecules into a three-dimensional network. Weak π-π contacts between the benzene and imidazole rings and between the benzene rings [centroid-centroid distances = 3.895 (1) and 3.833 (1) Å, respectively] may further stabilize the structure.