Supramolecular assembly of diethyl 1 H ‐pyrazole‐3,5‐dicarboxylate 0.33‐hydrate

In the title structure, C 9 H 12 N 2 O 4 ·0.33H 2 O, the molecules are present as two conformers, one of which is disordered. Another type of disorder involves N—N—H/H—N—N tautomerism. Two crystallographically independent water molecules reside on a threefold axis and some water H atoms are also disordered. Six diethyl 1 H ‐pyrazole‐3,5‐dicarboxylate molecules (three pairs of conformers) and two water molecules are assembled into a supramolecular aggregate via N—H⋯N, O w —H⋯N, O w —H⋯O w and N—H⋯O w hydrogen bonds.