3-(4-Chloro-phenyl-sulfon-yl)-8-methyl-1,3-diaza-spiro-[4.5]decane-2,4-dione.

In the title compound, C(15)H(17)ClN(2)O(4)S, the atoms in the hydantoin ring are coplanar (r.m.s. deviation = 0.006 Å). The crystal structure is stabilized by inter-molecular N-H⋯O hydrogen bonds which link the mol-ecules into centrosymmetric dimers. The dihedral angle subtended by the 4-chloro-phenyl group with the plane passing through the hydantoin unit is 82.98 (4)°. The cyclo-hexyl ring adopts an ideal chair conformation.