Bis(2-amino-4-methyl-pyrimidin-3-ium) trans-diaqua-bis-(pyrazine-2,3-di-car-boxylato)cobaltate(II) hexa-hydrate.

In the crystal structure of the mononuclear title compound, (C(5)H(8)N(3))(2)[Co(C(6)H(2)N(2)O(4))(2)(H(2)O)(2)]·6H(2)O or (ampymH)(2)[Co(pyzdc)(2)(H(2)O)(2)]·6H(2)O (ampym = 2-amino-4-methyl pyrimidine, pyzdcH(2) = pyrazine-2,3-dicarb-oxy-lic acid), the Co(II) ion is hexa-coordinated by two (pyzdc)(2-) groups in the equatorial plane and two water mol-ecules in axial positions, giving an N(2)CoO(4) bound set. The (pyzdc)(2-) anion acts as a bidentate ligand through one carboxyl-ate group O atom and pyrazine ring N atom. There are diverse N-H⋯ O and O-H⋯O and O-H⋯N hydrogen-bonding inter-actions, which lead to the formation of a three-dimensional supra-molecular architecture. Off-set or slipped π-π stacking inter-actions are also observed between adjacent pyrimidine rings with face-to-face distances of 3.6337†(9)†à .