title: 4-(4-Carb-oxy-1,3-thia-zol-2-yl)pyridinium 3-carb-oxy-4-hydroxy-benzene-sulfonate dihydrate.
abstract: In the crystal structure of the title compound, C(9)H(7)N(2)O(2)S(+)·C(7)H(5)O(6)S(-)·2H(2)O, an H atom from the 5-sulfosalicylic acid is transferred to the pyridyl N atom, forming a salt. The dihedral angle between the thiazole and pyridinium rings is 5.909 (5)°. The crystal packing is determined by O-H⋯O and N-H⋯O hydrogen bonds involving water mol-ecules.
authors.affiliation: Department of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang, Henan 471022, People's Republic of China.
authors.forename: Zhong-Xiang
authors.initials: ZX
authors.lastname: Du
authors.forename: Jun-Xia
authors.initials: JX
authors.lastname: Li