Mol­ecules of methyl 4-[(5-methyl-1H-pyrazol-3-yl)amino]-3-nitro­benzoate, C12H12N4O4, (I), exhibit a polarized (charge-separated) structure in the nitro­aniline portion. The mol­ecules are linked into chains of edge-fused R22(16) and R22(22) rings by a combination of N—H⋯O(carbon­yl) and C—H⋯O(nitro) hydrogen bonds. Methyl 1-(5-methyl-1H-pyrazol-3-yl)-1H-benzimidazole-5-carboxyl­ate, C13H12N4O2, (II), which is readily formed from (I) by reduction followed by ring formation, crystallizes with Z′ = 2 in the space group P\overline{1}. Each of the two independent mol­ecular types is linked into sheets of R44(28) rings by a combination of N—H⋯N and C—H⋯O(carbon­yl) hydrogen bonds.