In the title compound, C25H23BrN2O4, the seven-membered ring adopts a twisted-boat conformation. The indole ring system is planar within 0.021 (2) Å and the ester group [–C(=O)—O—C–] is almost coplanar with it [dihedral angle = 3.0 (2)°]. The conformation of the ester group is influenced by intra­molecular C—H⋯O inter­actions. In the crystal structure, mol­ecules are linked into chains along the b axis by C—H⋯N hydrogen bonds.

In the title compound, C26H25NO6S, the S atom shows a distorted tetra­hedral geometry, with O—S—O [119.46 (9)°] and N—S—C [107.16 (7)°] angles deviating from ideal tetra­hedral values, a fact attributed to the Thorpe–Ingold effect. The sulfonyl-bound phenyl ring forms dihedral angles of 41.1 (1) and 83.3 (1)°, respectively, with the formyl­phenyl and phenyl rings. The dihedral angle between formyl­phenyl and phenyl rings is 47.6 (1)°. The crystal packing features C—H⋯O hydrogen-bond inter­actions.