(+)-Brevione A. The first member of a novel family of bioactive spiroditerpenoids isolated from Penicillium brevicompactum Dierckx

(+)-Brevione A, the first member of a novel family of bioactive spiroditerpenoids, a potential allelopathic agent, has been isolated from the ethyl acetate active fractions of the aqueous acetone extracts of semi-solid fermented Penicillium brevicompactum Dierckx. The structure displays the novel spiroditerpenoid skeleton of breviane. The structure elucidation of brevione A was performed by homo- and hetero-nuclear 2D NMR spectral data. On the basis of combined studies of the theoretical conformations and NOEDIFF data, its relative stereochemistry is proposed.