Isolation and structural elucidation of eight new related analogues of the mycotoxin (-)-botryodiplodin from Penicillium coalescens.

Bioassay-guided fractionation of the organic extract derived from the terrestrial fungus Penicillium coalescens led to the isolation of the known mycotoxin (-)-botryodiplodin (1) and eight new structurally related analogues (2-9). The structures of the novel compounds were determined by MS and NMR studies, including 1D and 2D NMR. A likely biogenetic pathway from the aldehydic open form of 1 (C7 unit, U1) is proposed for these metabolites. Among all the isolated metabolites, only (-)-1 showed antifungal, antibacterial, and insecticidal activity. This latter activity appears to be a new property attributed to (-)-1.