2-Amino-5-bromo-pyridinium 6-oxo-1,6-dihydro-pyridine-2-carboxyl-ate monohydrate.

In the crystal structure of the title salt, C(5)H(6)BrN(2) (+)·C(6)H(4)NO(3) (-)·H(2)O, the protonated N atom and the 2-amino group of the cation are hydrogen bonded to the carboxyl-ate O atoms of the anion via a pair of N-H⋯O hydrogen bonds, forming an R(2) (2)(8) ring motif. The ion pairs are further connected via O-H⋯O, N-H⋯O, N-H⋯Br and C-H⋯O hydrogen bonds, forming a two-dimensional network parallel to the bc plane. The water mol-ecules self-assemble through O-H⋯O hydrogen bonds, forming one-dimensional supra-molecular chains along the a axis, with graph-set notation C(2) (2)(4).