Stagonolides B-F, nonenolides produced by Stagonospora cirsii, a potential mycoherbicide of Cirsium arvense.
Stagonospora cirsii, a fungal pathogen isolated from Cirsium arvense and proposed as a potential mycoherbicide of this perennial noxious weed, produces phytotoxic metabolites in liquid and solid cultures. Recently, the main metabolite, stagonolide (1), with interesting phytotoxic properties, was isolated from a liquid culture and characterized as a new nonenolide. In the present work this same fungus, grown in solid culture, exhibited an increased capacity to produce nonenolides. Five new nonenolides, named stagonolides B-F (2-6), were isolated and characterized using spectroscopic methods. When tested by a leaf disk puncture assay at a concentration of 1 mg/mL, these compounds showed no toxicity to C. arvense and Sonchus arvensis, whereas stagonolide (1) was highly toxic. Stagonolide (1) and stagonolide C (3) were weakly toxic to Colpoda steinii, a protozoan, when tested at 0.05 mg/mL, with the other stagonolides nontoxic. A number of structure-activity relationship observations were made.
Evidente
Antonio
A
Dipartmento di Sciencze del Suolo, della Pianta, dell'Ambiente e delle Produzioni Animali, Università di Napoli Federico II, Porici, Italy. evidente@unina.it
Cimmino
Alessio
A
Berestetskiy
Alexander
A
Mitina
Galina
G
Andolfi
Anna
A
Motta
Andrea
A
D001203:Ascomycota / Q000737:chemistry*; D031180:Cirsium / Q000187:drug effects*; D006540:Herbicides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D006573:Heterocyclic Compounds, 1-Ring / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D007783:Lactones / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D018515:Plant Leaves / Q000737:chemistry; D013329:Structure-Activity Relationship
D006540:Herbicides; D006573:Heterocyclic Compounds, 1-Ring; D007783:Lactones; C527511:stagonolide