The title compound, C(10)H(12)O(5)N(2), crystallizes with two independent molecules in the asymmetric unit. The molecules in the crystal structure are arranged into one-dimensional substructural ribbon motifs stabilized by a combination of two O-H...O and three N-H...O intermolecular hydrogen bonds, and also augmented by short C=O...C=O carbonyl-carbonyl interactions. Two intermolecular C-H...O short contacts between adjacent ribbons generate complex two-dimensional sheets on the ab plane. Adjacent sheets are linked via C-H...pi(arene) interactions, resulting in a complex three-dimensional framework.