Phyllostictines A-D, oxazatricycloalkenones produced by Phyllosticta cirsii, a potential mycoherbicide for Cirsium arvense biocontrol

From the liquid culture of Phyllosticta cirsii four new oxazatricycloalkenones, named phyllostictine A-D (1-4), were isolated, and chemically and biologically characterized. Three of them (1, 2, and 4) proved to have interesting herbicidal activity.