Ethyl 5-amino-1-(4-chloro-2-nitro-phen-yl)-1H-pyrazole-4-carboxyl-ate.

In the mol-ecule of the title compound, C(12)H(11)ClN(4)O(4), the pyrazole ring is coplanar with the amino and ethoxy-carbonyl groups within 0.026 (2) and 0.105 (2) Å, respectively. The C(6) ring of the 4-chloro-2-nitro-phenyl group is twisted by 53.58 (4)° relative to the plane of the pyrazole ring. The planar structure of the pyrazole ring is stabilized by an intra-molecular N-H⋯O hydrogen bond between its substituents. Neighbouring mol-ecules are linked through inter-molecular N-H⋯N and N-H⋯O hydrogen bonds, giving rise to one-dimensional tapes along the b axis. Mol-ecules in the chain are linked to those of an adjacent chain through weak C-H⋯O inter-actions, forming a three-dimensional network.