Abstract
Lenthionine, an odorous substance, has been isolated from Lentinus edodes (Berk.) Sing and the structure was established as 1, 2, 3, 5, 6-pentathiepane (I). 1, 2, 4, 6-Tetrathiepane (II) and 1, 2, 3, 4, 5, 6-hexathiepane (III) were also isolated from the mushroom in minor quantities. All these cyclic methylene polysulfides were synthesized from simple starting materials. A precursor of lenthionine was isolated in crystalline form and the structure was deduced mainly on the mass spectral studies. A possible mechanism for the formation of lenthionine and its analogs from the precursor was proposed.