The conformational analysis of several 2-substituted 1, 3-dithianes made possible the evaluation of SCY anomeric interactions, where Y= SCH3, SC6H5, CO2CH3, CO6H5, CO2H and N (CH3) 2. The relative magnitude of the effects observed for these groups [ΔG° dithiane (Y)-ΔGδ cyclohexane (Y)] can be explained in terms of the combined influence of dipole/dipole and two-electron stabilizing interactions (stereoelectronic effect).