title: Phytotoxins produced by Phoma chenopodiicola, a fungal pathogen of Chenopodium album.
abstract: Two phytotoxins were isolated from the liquid culture of Phoma chenopodiicola, a fungal pathogen proposed for the biological control of Chenopodium album, a common worldwide weed of arable crops. The two phytotoxins appeared to be a new tetrasubstituted furopyran and a new ent-pimaradiene. From the same culture a new tetrasubstituted isocoumarin was also isolated. These compounds were characterized by using spectroscopic (essentially 1D and 2D NMR and HR ESI MS) and chemical methods as 3-(3-methoxy-2,6-dimethyl-7aH-furo[2,3-b]pyran-4-yl)-but-2-en-1-ol (chenopodolan D, 1) (1S,2S,3S,4S,5S,9R,10S,12S,13S)-1,3,12-triacetoxy-2,hydroxy-6-oxo-ent-pimara-7(8),15-dien-18-oic acid 2,18-lactone (chenopodolin B, 3), and, 4,5,7-trihydroxy-3-methyl-isochroman-1-one (chenisocoumarin, 2) The absolute configuration of chenisocoumarin was assigned by applying an advanced Mosher's method through the derivatization of its secondary hydroxylated carbon C-4, while that of chenopodolan D by application of quantum mechanical calculations of chiroptical (ECD and ORD) properties. When assayed by leaf puncture against non-host weeds, chenopodolan D and chenopodolin B showed phytotoxicity while chenisocoumarin and the 9-O-acetyl derivative of chenopodolan D were inactive. These results confirm that the nature of the side chain at C-4 in chenopodolans, and in particular its hydroxylation, are important features for activity. The activity of chenopodolin B could also be explained by its possible hydrolysis to chenopodolin.
authors.affiliation: Department of Chemical Sciences, University of Naples "Federico II", Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Evidente
authors.affiliation: Department of Chemical Sciences, University of Naples "Federico II", Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy.
authors.forename: Alessio
authors.initials: A
authors.lastname: Cimmino
authors.affiliation: Institute of Sciences of Food Production, National Research Council, Via Amendola 122/O, 70125 Bari, Italy.
authors.forename: Maria Chiara
authors.initials: MC
authors.lastname: Zonno
authors.affiliation: Department of Chemical Sciences, University of Naples "Federico II", Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Masi
authors.affiliation: All-Russian Institute of Plant Protection, Russian Academy of Agricultural Sciences, Pushkin, Saint-Petersburg 196608, Russia.
authors.forename: Alexander
authors.initials: A
authors.lastname: Berestetskyi
authors.affiliation: Department of Sciences, University of Basilicata, Via dell'Ateneo Lucano 10, 85100 Potenza, Italy.
authors.forename: Ernesto
authors.initials: E
authors.lastname: Santoro
authors.affiliation: Department of Sciences, University of Basilicata, Via dell'Ateneo Lucano 10, 85100 Potenza, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Superchi
authors.affiliation: Institute of Sciences of Food Production, National Research Council, Via Amendola 122/O, 70125 Bari, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Vurro
authors.affiliation: Department of Chemical Sciences, University of Naples "Federico II", Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy. Electronic address: evidente@unina.it.
authors.forename: Antonio
authors.initials: A
authors.lastname: Evidente
mesh_terms: D045784:Abietanes / Q000737:chemistry / Q000494:pharmacology; D001203:Ascomycota / Q000737:chemistry* / Q000378:metabolism* / Q000472:pathogenicity; D027463:Chenopodium album / Q000382:microbiology; D005663:Furans / Q000737:chemistry / Q000494:pharmacology; D006540:Herbicides / Q000737:chemistry / Q000494:pharmacology*; D049934:Isocoumarins / Q000737:chemistry / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009183:Mycotoxins / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology*; D018515:Plant Leaves / Q000187:drug effects; D057685:Plant Weeds / Q000187:drug effects; D011714:Pyrans / Q000737:chemistry / Q000494:pharmacology; D021241:Spectrometry, Mass, Electrospray Ionization; D013329:Structure-Activity Relationship
chemical_list: C000608328:1,3,12-triacetoxy-2-hydroxy-6-oxopimara-7(8),15-dien-18-oic acid 2,18-lactone; C000608327:3-(3-methoxy-2,6-dimethyl-7aH-furo(2,3-b)pyran-4-yl)-but-2-en-1-ol; C000608329:4,5,7-trihydroxy-3-methylisochroman-1-one; D045784:Abietanes; D005663:Furans; D006540:Herbicides; D049934:Isocoumarins; D009183:Mycotoxins; D011714:Pyrans
keywords: Chenopodium album; Furopyrans; Herbicides; Isocoumarines; Phoma chenopodiicola; Phytotoxins; ent-Pimaradiene