The asymmetric unit of the title compound, C(6)H(9)N(2) (+)·C(6)H(4)NO(2) (-)·0.63H(2)O, contains two crystallographically independent 2-amino-5-methyl-pyridinium cations, a pair of picolinate anions and two water mol-ecules, one with an occupancy of 0.25. Both the 2-amino-5-methyl-pyridine mol-ecules are protonated at the pyridine N atoms. In the crystal structure, the cations, anions and water mol-ecules are linked via N-H⋯O, N-H⋯N and O-H⋯O hydrogen bonds, as well as by C-H⋯O contacts, forming a chain along the b axis. In addition, weak π-π inter-actions are observed between pyridinium rings, with centroid-centroid distances of 3.5306 (13) Å.
* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.