In the title mol-ecule, C(19)H(17)N(3)O(6), the indole ring system is essentially planar (r.m.s. deviation = 0.009 Å) and forms a dihedral angle of 31.96 (9)° with the nitro-substituted benzene ring. In the crystal, mol-ecules are linked by pairs of N-H⋯O hydrogen bonds, forming inversion dimers which are connected by further N-H⋯O hydrogen bonds into a two-dimensional network parallel to (102).