Two new phytotoxic polyketides, tagetolone (1) and tagetenolone (2), in add
ition to tyrosol and p-hydroxybenzoic acid, have been isolated from the org
anic crude extract of culture filtrates from the fungal pathogen Alternaria
tagetica. Complete characterization of all structures was carried out foll
owing a careful analysis of their spectroscopic data (IR, MS, H-1 and C-13
NMr, and 2D NMR experiments).