Secondary mould metabolites. Part 34. Isolation and structure elucidation of illudosin, a novel sesquiterpene from Clitocybe illudens using one and two dimensional NMR techniques

Abstract

The structure of illudosin 1, a novel sesquiterpene isolated from the still liquid cultures of Clitocybe illudens(=Omphalotus olearius), has been asssigned on the basis of ¹H and ¹³C NMR spectroscopic studies, including ¹H–¹³C heteronuclear correlation spectra (HETCOR and COLOC). The preferred conformation and the absolute configuration of the metabolite were deduced from NOE experiments and the application of the exciton chirality method on the dibenzoate 2. Illudosin may be regarded as an intermediate in the biosynthesis of the fomannosin 3.