2,6-Diaminopyridinium bromide monohydrate

In the title compound, [C5H6N3]Br.H2O, the 2,6-diaminopyridine is protonated on the ring N atom. The cation is planar. The moieties are held together by extensive hydrogen bonding and by pi-pi interactions. The bromide ion is hydrogen bonded, as acceptor, to two H2O molecules, with an average Br...H-O(H2O) distance of 3.322 (11) Angstrom, to the ring N atom Br...N-H(NH) 3.353 (3) Angstrom, and to four amino N atoms, with an average Br...H-N(NH2) 3.63 (14) Angstrom. The water molecule bonds, as acceptor, to the pyridine N atom O...H-N(NH2) 2.583 (5) Angstrom. The closest pi-pi interaction is between pyridine ring planes, with an interplanar spacing 3.358 Angstrom apart.