The mol-ecule of the title compound, C(14)H(19)N(3)O(7)·0.5H(2)O, exhibits an E conformation about the C=N double bond. The water mol-ecule possesses crystallographically imposed twofold symmetry. In the crystal structure, the mol-ecules are connected by inter-molecular O-H⋯O and N-H⋯O hydrogen bonds into a three-dimensional network.