Metabolites of the Higher Fungi. Part 32. Rosnecatrone, a Phytotoxic Bicyclo[4.1.0]hept-3-en-2-one from the Fungus Rosellinia necatrix Prill.

Rosnecatrone 7 is a phytotoxic metabolite isolated from cultures of a virulent strain of the fungus Rosellinia necatrix. The compound is identified as 5-hydroxy-4-hydroxymethyl-1-(1-hydroxy-3-methylbut-2-enyl)-3-[(E)-propenyl]-7-oxabicyclo[4.1.0]hept-3-en-2-one by chemical and physical methods. The absolute configuration is determined and the X-ray structure of its borohydride reduced derivative, rosnecatrol 10 as the tetra-acetate is described.