BIOSYNTHESIS OF SESQUITERPENES OF CADINANE TYPE IN CULTURED-CELLS OF HETEROSCYPHUS-PLANUS

A set of differently deuterated mevalonates ([6,6,6-2-H-2(3)]-, [5,5-H-2(2)]-, [4,4-H-2(2)] and [2,2-H-2(2)]-) was shown to be incorporated effectively into cadinanes including (1S)-7-methoxy-1,2-dihydrocadalene and (1S,4R)-7-hydroxycalamenene in suspension cultures of the liverwort, Heteroscyphus planus. Distributions of H-2 atoms in the biosynthetically deuterated cadinanes (isotopic purities: ca 20-30%) were determined by their mass spectra and mass chromatograms. The labelling patterns in both 7-methoxy-1,2-dihydrocadalene and 7-hydroxycalamenene indicate 1,2- and 1,3-hydride shifts in their formation. It is also concluded that a NIH shift did not occur in the hydroxylation of an aromatic ring of calamenene to form 7-hydroxycalamenene.