2,3-Diaminopyridinium 3-carboxy-4-hydroxybenzenesulfonate monohydrate

In the title hydrated molecular salt, C5H8N3 +·C7H5O6S−·H2O, the ion pairs and water molecules are connected by N—H⋯O, O—H⋯O and C—H⋯O hydrogen bonds, thereby forming a three-dimensional network. There is an intramolecular O—H⋯O hydrogen bond in the 3-carboxy-4-hydroxybenzenesulfonate anion, which generates an S(6) ring motif.