(2-Amino-7-methyl-4-oxidopteridine-6-carboxyl­ato-κ(3) O (4),N (5),O (6))(ethane-1,2-diamine-κ(2) N,N′)(1H-imidazole-κN (3))nickel(II) dihydrate

In the title complex, [Ni(C(8)H(5)N(5)O(3))(C(2)H(8)N(2))(C(3)N(2)H(4))]·2H(2)O, a tridentate 2-amino-7-methyl-4-oxidopteridine-6-carboxyl­ate (pterin) ligand, a bidentate ancillary ethane-1,2-diamine (en) ligand and a monodentate 1H-imidazole (im) ligand complete a distorted octa­hedral geometry around the Ni(II) atom. The pterin ligand forms two chelate rings. Both the en and im ligands are arranged nearly orthogonally relative to the pterin ligand [dihedral angles between the mean planes of the en and pterin ligands and of the im and pterin ligands are 84.62 (9) and 85.14 (9)°, respectively]. N—H⋯N, N—H⋯O, O—H⋯N and O—H⋯O hydrogen bonds link the complex mol­ecules and lattice water mol­ecules into a three-dimensional network.