Experimental

R factor = 0.031; wR factor = 0.090; data-to-parameter ratio = 14.4. In the title compound, C17H24N2O5S2, the indole ring system is nearly planar [maximum deviation = 0.032 (1) Å] and the cyclohexene ring has a half-chair conformation. In the crystal, N—H O hydrogen bonds link the molecules into a chain running along the b-axis direction. Weak C—H O hydrogen bonds and weak C—H interactions are observed between the chains. Related literature For tetrahydrocarbazole systems present in the framework of a number of indole-type alkaloids of biological interest, see: Saxton (1983). For the antitumor activity of tetrahydro-carbazoles containing an amine unit, see: Chen et al. (2009). For the most potent drugs, such as ellipcitine and olivacine, for the treatment of a variety of cancers, see: Pelletier (1970). For the use of tetrahydrocarbazoles in the synthesis of pyrido-carbazoles, see: Knölker & Reddy (2002). For related struc