4-{(4<i>Z</i>)-4-[(2<i>Z</i>)-3-(4-Fluoroanilino)-1-hydroxybut-2-en-1-ylidene]-3-methyl-5-oxo-4,5-dihydro-1<i>H</i>-pyrazol-1-yl}benzenesulfonamide

In the title compound, C(20)H(19)FN(4)O(4)S, the pyrazole and benzene-sulfonamide rings are coplanar [dihedral angle = 5.02 (15)°] but this planarity does not extend over the entire mol-ecule, the dihedral angle between the terminal six-membered rings being 33.24 (14)°. Intra-molecular hy-droxy-hy-droxy O-H⋯O and amine-hy-droxy N-H⋯O hydrogen bonds, as a well as a tight C-H⋯O(carbon-yl) inter-action, lead to a sequence of three fused S(6) rings. Supra-molecular chains along the a axis feature in the crystal packing; these chains are stabilized by amine-sulfonamide N-H⋯O and amine-pyrazole N-H⋯N hydrogen bonds.