2-Amino-4-methylpyridinium 3-carboxy-4-hydroxybenzenesulfonate monohydrate

Abstract

In the crystal structure of the title salt, C6H9N2+·C7H5O6S−·H2O, the water molecule acts as an acceptor of bifurcated N—H...O hydrogen bonds from the pyridinium H atom and one H atom of the 2-amino group, forming an R21(6) ring. The 3-carboxy-4-hydroxybenzenesulfonate anions self-assemble via O—H...O hydrogen bonds, leading to supramolecular chains along the a axis. These chains and R21(6) motifs are linked via O—H...O, N—H...O and C—H...O hydrogen bonds, forming a layer parallel to the ac plane. There is also an intramolecular O—H...O hydrogen bond in the 3-carboxy-4-hydroxybenzenesulfonate anion, generating an S(6) ring motif.