title: C-5-substituted antifeedant silphinene sesquiterpenes from Senecio palmensis.
abstract: The new sesquiterpenes, 5alpha-senecioyloxysilphinen-3-one (5), 5alpha-tigloyloxysilphinen-3-one (7), and 3beta-hydroxy-5alpha-angeloyloxysilphinene (8), and the known compounds (6S)-2,10-bisaboladien-1-one (1), 6,7-epoxy-3(15)-caryophyllene (2), 6,7-epoxy-2,9-humuladiene (3), 5alpha-angeloyloxysilphinen-3-one (4), and 5alpha-acetoxysilphinen-3-one (6) were isolated from bioactive fractions of Senecio palmensis. The structures of these compounds were established by spectroscopic analysis and chemical evidence. The semisynthetic analogues silphinen-3,5-dione (9), 5alpha-hydroxysilphinen-3-one (10), 5beta-hydroxysilphinen-3-one (11), 5beta-acetoxysilphinen-3-one (12), and 5beta-isobutyryloxysilphinen-3-one (13) were generated to carry out a structure-activity study on the antifeedant action of these molecules against several divergent insect species.
authors.affiliation: Instituto de Productos Naturales y Agrobiología, CSIC, Avenida Astrofísico F. Sánchez, 3, 38206 La Laguna, Tenerife, Spain.
authors.forename: Matías
authors.initials: M
authors.lastname: Reina
authors.forename: Matthias
authors.initials: M
authors.lastname: Nold
authors.forename: Omar
authors.initials: O
authors.lastname: Santana
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Orihuela
authors.forename: Azucena
authors.initials: A
authors.lastname: González-Coloma
mesh_terms: D000818:Animals; D019659:Asteraceae / Q000737:chemistry*; D005247:Feeding Behavior / Q000187:drug effects*; D006458:Hemolymph / Q000378:metabolism; D007313:Insecta / Q000187:drug effects; D008954:Models, Biological; D019906:Nuclear Magnetic Resonance, Biomolecular; D010946:Plants, Medicinal / Q000737:chemistry*; D012717:Sesquiterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D013030:Spain; D013329:Structure-Activity Relationship
chemical_list: D012717:Sesquiterpenes