5-Nitro-1-nonyl-1H-benzimidazol-2(3H)-one.

In the title mol-ecule, C(16)H(23)N(3)O(3), the dihedral angle between the benzimidazole and nitro group planes is 5.34†(9)° and the dihedral angle between the benzimidazole and aliphatic chain mean planes is 73.23†(5)°. The C-C-C-C torsion angles (about 176°) of the nonyl group indicate an all-anti-periplanar conformation. In the crystal, adjacent mol-ecules are linked by pairs of N-H⋯O hydrogen bonds into inversion dimers. These mol-ecules are further connected through C-H⋯O inter-actions, building tapes parallel to (22).