The nitrate dihydrate of an aqua­dicopper(II) complex cation with guanidino­acetic acid and a novel trianionic disubstituted guanidine as ligands at 120 K

The structure of the title compound, aqua­μ‐(N¹‐carboxylato­methyl­guanidino)­oxidoacetato](μ‐guanidino­acetic acid)­di­copper(II) nitrate dihydrate, Cu₂(C₅H₆N₃O₅)(C₃H₇N₃O₂)(H₂O)]NO₃·2H₂O, contains two enantiomers of the di­copper(II) complex cation that comprise water, neutral zwitterionic guanidino­acetic acid and the trianion of (N¹‐carboxy­methyl­guanidino)­hydroxy­acetic acid as ligands. Extensive hydrogen bonding creates three‐dimensional connectivity but is largely confined to layers that each contain both cation enantiomers. These layers are related to one another by crystallographic symmetry and are therefore identical in composition and connectivity.