Pentathiepanes are organosulfur compounds and sulfur heterocycles with the formula . Three isomers exist depending on the location of the C atoms in the ring. These compounds are uncommon except for the 1,4-derivative, which is called lenthionine. It contributes to the aroma of shiitake mushroooms.
More common than the pentathiepanes are pentathiepines, which have a C=C bond in the ring. Only one isomer exists for this class of rings.