In the title compound, C8H7N3O4 (systematic name: 4-nitro­benzene-1,2-dicarboxamide), each of the substituents is twisted out of the plane of the benzene ring to which it is attached [dihedral angles of 11.36 (2)° for the nitro group, and 60.89 (6) and 34.39 (6)° for the amide groups]. The amide groups are orientated to either side of the least-squares plane through the benzene ring with the amine groups being directed furthest apart. In the crystal, a three-dimensional architecture is established by a network of N—H⋯O hydrogen bonds.

In the title compound, C11H6N2O {systematic name: 3-(prop-2-yn-1-yl­oxy)benzene-1,2-dicarbo­nitrile}, the 14 non-H atoms are approximately coplanar (r.m.s. deviation = 0.051 Å) with the terminal ethyne group being syn with the adjacent cyano residue. In the crystal, centrosymmetric dimers are connected by pairs of C—H⋯N inter­actions and these are linked into a supra­molecular tape parallel to (1-30) via C—H⋯N inter­actions involving the same N atom as acceptor.

In the title compound, C8H3N3O2 (systematic name: 4-nitro­benzene-1,2-dicarbo­nitrile), the nitro group is twisted out of the plane of the benzene ring to which it is attached [O—N—Cring—Cring torsion angle = 9.80 (13)°]. In the crystal packing, supra­molecular layers with a zigzag topology in the ac plane are sustained by C—H⋯N inter­actions.