2-[(E)-({4-[(4,6-Dimethylpyrimidin-2-yl)sulfamoyl]phenyl}iminio)methyl]-6-hydroxyphenolate

Abstract

The title compound, C19H18N4O4S, exists as a zwitterion in the solid state, with nominal proton transfer from a phenol group to the imine N atom. The 2,3-dihydroxybenzaldehyde fragment is oriented at a dihedral angle of 35.51 (11)° to the adajacent aniline group and makes a dihedral angle of 76.99 (6)° with the 4,6-dimethylpyrimidin-2-amine group. Intramolecular O—H...O and N—H...O hydrogen bonds close S(5) and S(6) rings, respectively; the same O atom accepts both bonds. In the crystal, polymeric chains along [001] are formed from molecules joined end-to-end by N—H...O and O—H...N hydrogen bonds; these feature R23(6) loops. The polymeric chains are linked by C—H...O interactions and there are π–π interactions between the pyrimidine rings with a centroid–centroid distance of 3.446 (2) Å.