Glycinium hydrogen fumarate glycine solvate monohydrate.

In the title compound, C(2)H(6)NO(2) (+)·C(4)H(3)O(4) (-)·C(2)H(5)NO(2)·H(2)O, the asymmetric unit contains two glycine residues, one protonated and one in the zwitterionic form, a hydrogen fumarate anion and a water mol-ecule. Through N-H⋯O and O-H⋯O hydrogen bonds, mol-ecules assemble in layers parallel to the (10) plane, one layer of hydrogen fumarate anions alternating with two layers of glycine mol-ecules. In each glycine layer, hydrogen bonds generate an R(4) (4)(19) graph-set motif. Further hydrogen bonds involving the water mol-ecule and the hydrogen fumarate anions result in the formation of a three-dimensional network.