[Figure not available: see fulltext.] The reactions of 2-benzylidene-3-methyl-4-nitro-2,5-dihydrothiophene 1,1-dioxides with dimedone were used to synthesize a series of tricyclic compounds containing fused nitrosulfolane and octahydrochromenone rings. The structural features of the obtained polycyclic compounds were established on the basis of IR and NMR spectra, as well as X-ray structural analysis.