2-Amino-3-carb­oxy­pyridinium chloride hemihydrate

The asymmetric unit of the title compound, C6H7N2O2+·Cl−·0.5H2O, consists of two protonated 2-amino-3-carb­oxy­pyridine cations, two chloride anions and one mol­ecule of water. The crystal packing can be described as alternating layers of cations and anions parallel to (110), which are linked together by Ow—H⋯Cl inter­actions. In the crystal, four types of classical hydrogen bonds are observed, viz. cation–anion (O—H⋯Cl and N—H⋯Cl), cation–cation (N—H⋯O), cation–water (N—H⋯Ow) and water–anion (Ow—H⋯Cl), resulting in the formation of an infinite three-dimensional network.