2,2′-Imino­diethanaminium 2,2′-(disulfanyldi­yl)dibenzoate dihydrate

In the title hydrated salt, C(4)H(15)N(3) (2+)·C(14)H(8)O(4)S(2) (−)·2H(2)O, the dication (with both terminal –NH(2) groups protonated) adopts a U-shaped conformation, the N(amine)—C—C—N(aza­nium) torsion angles being 57.9 (6) and 60.3 (6)°. The dianion is twisted: the central C—S—S—C torsion angle is 81.3 (2)° and the dihedral angle between the benzene rings is 85.4 (3)°. In the crystal, a chain in the a-axis direction mediated by water–carboxyl­ate O—H⋯O hydrogen bonds through a sequence of alternating 12-membered {⋯OCO⋯HOH}(2) and eight-membered {⋯O⋯HOH}(2) synthons occurs, which involves only one of the carboxyl­ate residues. The second carboxyl­ate residue participates in N—H⋯O hydrogen bonding, generating a three-dimensional network, along with aza­nium–water N—H⋯O hydrogen bonds.