(2-Amino-7-methyl-4-oxido­pteridine-6-carboxyl­ato-κ³O⁴,N⁵,O⁶)aqua(1,10-phen­an­thro­line-κ²N,N′)cobalt(II) trihydrate

In the title compound, [Co(C₈H₅N₅O₃)(C₁₂H₈N₂)(H₂O)]·3H₂O, a tridentate 2-amino-7-methyl-4-oxidopteridine-6-carboxyl­ate ligand, a bidentate ancillary 1,10-phenanthroline (phen) ligand and a water mol­ecule complete a distorted octa­hedral geometry around the Co^II atom. The pterin ligand forms two chelate rings. The phen and pterin ring systems are nearly perpendicular [dihedral angle = 85.15 (8)°]. N—H...O, O—H...N and O—H...O hydrogen bonds link the complex mol­ecules and lattice water mol­ecules into a layer parallel to (001). π–π stacking contacts (involving phen–phen and pteridine–pteridine) are also observed [centroid–centroid distances = 3.670 (2), 3.547 (2), 3.698 (2) and 3.349 (2) Å].