5'-Amino-2-oxo-2',3'-dihydro-spiro-[indoline-3,7'-thieno[3,2-b]pyran]-6'-carbonitrile 1',1'-dioxide.

In the title compound, C(15)H(11)N(3)O(4)S, the dihedral angle between the mean planes of the dihydro-indol-2-one (r.m.s. deviation = 0.015 Å) and dihydro-thieno[3,2-b]pyran (r.m.s. deviation = 0.011 Å) ring systems is 89.53 (3)°. The crytal packing is consolidated by inter-molecular N-H⋯O and N-H⋯N hydrogen bonds, which link the mol-ecules into a two-dimensional network into sheets lying parallel to (100).