Hydrogen-bonding patterns in 2-amino-4,6-dimethylpyrimidinium hydrogen sulfate

In the title compound, C6H10N3+.HSO4-, the asymmetric unit consists of a hydrogen sulfate anion and a 2-amino-4,6-dimethylpyrimidinium cation. The hydrogen sulfate anions self-assemble through O-H...O hydrogen bonds, forming supramolecular chains along the b axis, while the organic cations form base pairs via N-H...N hydrogen bonds. The aminopyrimidinium cations join to the sulfate anions via a pair of hydrogen bonds donated from the pyrimidinium protonation site and from the exo amine group cis to the protonated site.