In the title compound, C(14)H(12)N(2)O(6), the half mol-ecule in the asymmetric unit of the cell is completed by a crystallographic twofold rotation axis, and the two benzene rings of the complete mol-ecule make a dihedral angle of 60.5 (3)°. Furthermore, inter-molecular weak C-H⋯O hydrogen bonds link adjacent mol-ecules, forming a two-dimensional sheet. These sheets are stablized by face-to-face weak π-π contacts [centroid-centroid distance = 3.682 (1) Å] between the nearly parallel [dihedral angle = 0.12 (7)°] benzene rings of the neighboring mol-ecules, resulting in a three-dimensional network.