In the title compound, C(18)H(21)N(3)O(6), a pyrimidine derivative, the dihedral angle between the benzene and pyrimidine rings is 52.26 (12)°. The carboxyl-ate unit is twisted with respect to the pyrimidine ring, making a dihedral angle of 12.33 (7)°. In the crystal, mol-ecules are linked by a pair of O-H⋯O hydrogen bonds, forming an inversion dimer. The dimers are stacked into columns along the b axis through weak C-H⋯O inter-actions.