title: Studies on structure-activity relationship of sphaeropsidins A-F, phytotoxins produced by Sphaeropsis sapinea f. sp. cupressi.
abstract: Six forms of sphaeropsidins (SA-SF), three- and tetra-cyclic unrearranged pimarane diterpenes produced by Sphaeropsis sapinea f. sp. cupressi, as well as eight derivatives obtained by chemical modification of SA-SC, were assayed for their bioactivity. The effect of each compound on plants which are host or non-host of the pathogen was investigated. Activity on some plant pathogenic fungi was also tested. Some structure-activity relationships have been identified for both phytotoxic and antifungal activity. It appears that the integrity of the tricyclic pimarane system, the preservation of the double bond C(8)-C(14), the tertiary hydroxyl group at C-9, the vinyl group at C-13, and the carboxylic group at C-10 as well as the integrity of the A-ring provide these molecules with non selective phytotoxic and antimycotic activity.
authors.affiliation: Dipartimento di Biologia e Patologia Vegetale, Università di Bari, I-70126, Bari, Italy. sparlor@agr.uniba.it
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Sparapano
authors.forename: Giovanni
authors.initials: G
authors.lastname: Bruno
authors.forename: Olga
authors.initials: O
authors.lastname: Fierro
authors.forename: Antonio
authors.initials: A
authors.lastname: Evidente
mesh_terms: D000935:Antifungal Agents / Q000737:chemistry / Q000494:pharmacology; D001681:Biological Assay; D029781:Cupressus / Q000737:chemistry* / Q000187:drug effects / Q000382:microbiology; D004224:Diterpenes / Q000737:chemistry* / Q000494:pharmacology*; D007887:Fabaceae / Q000187:drug effects; D005658:Fungi / Q000187:drug effects / Q000235:genetics; D018551:Solanum lycopersicum / Q000187:drug effects; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010935:Plant Diseases / Q000382:microbiology; D013329:Structure-Activity Relationship; D018675:Toxicity Tests
chemical_list: D000935:Antifungal Agents; D004224:Diterpenes