4-(2-Hydroxyethyl)anilinium 3-carboxy-4-hydroxybenzenesulfonate monohydrate

In the structure of the title compound, C8H12NO+·C7H5O6S−·H2O, isolated from the reaction of 2-(4-aminophenyl)ethanol with 5-sulfosalicylic acid, the cations form head-to-tail hydrogen-bonded chains through C11(9) anilinium N+—H...Ohydroxyl interactions while the anions also form parallel but C11(8)-linked chains through carboxylic acid O—H...Osulfonate interactions. These chains inter-associate through a number of N+—H...O and O—H...O bridging interactions, giving a two-dimensional array in the ab plane