Metabolic products of Stemphylium radicinum. Part IV. Minor products

Abstract

Pyrenophorol, dehydrocurvularin, and a new C₉H₁₂O₃ compound, shown to be 2,3-dihydro-2-hydroxy-2,4-dimethyl-5-trans-propenylfuran-3-one, have been isolated in low yield from culture filtrates of the phytopathogenic fungus Stemphylium radicinum, C.M.I. 105654, in addition to radicinin and pyrenophorin which were obtained previously. The pyrenophorin was sometimes accompanied by an isomeric compound, possibly an artifact derived from it by an intramolecular Michael condensation.