Access to 2,3-diaryl-4-nitrothiochroman S,S-dioxides from 3-nitrobenzo[b]thiophene

The base-induced cyclization of (E)-2-aryl-1-[2-(benzylsulfonyl)phenyl]-1-nitroethenes to polysubstituted thiochroman S,S-dioxides exhibits a diastereoselectivity that can be oriented towards a selected isomer by means of appropriate adjustments of the experimental conditions. The interest of such a result also rests on the promising pharmacological activity of the products, whose structure encompasses different well-acknowledged pharmacophores. A conformational 1H NMR investigation, backed by molecular-mechanics calculations, has also been accomplished.