title: Eudesmanes from Pluchea sagittalis. Their antifeedant activity on Spodoptera frugiperda.
abstract: Eudesmane-type sesquiterpenoids 3alpha-(2,3-epoxy-2-methylbutyryloxy)-4alpha-formoxy-11-hydroxy-6,7-dehydroeudesman-8-one (1) and 3alpha-(2,3-epoxy-2-methylbutyryloxy)-4alpha,7alpha,11-trihydroxyeudesman-8-one (2), together with 10 known structurally related eudesmanes were isolated from the CHCl3 extract of aerial parts of Pluchea sagittalis (Lamarck) Cabrera. Their structures were deduced by extensive application of 1 and 2D NMR spectroscopic techniques and high and low resolution CIMS. X-ray crystallographic analysis of the known compound 3alpha-(2,3-epoxy-2-methylbutyryloxy)-4alpha-formoxycuauthemone (9) is reported here for the first time, and confirms the structural features for the series of the reported eudesmanes. All eudesmanes were tested for their antifeedant activity by incorporating them to an artificial diet of larvae of the polyphagous insect Spodoptera frugiperda at a concentration of 100ppm. Our results, from feeding choice tests, indicated that most of the compounds deter larval feeding at the cited concentration.
authors.affiliation: Instituto de Química Orgánica, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Ayacucho 471, 4000 Tucumán, Argentina.
authors.forename: Nancy
authors.initials: N
authors.lastname: Vera
authors.forename: Rosana
authors.initials: R
authors.lastname: Misico
authors.forename: Manuel González
authors.initials: MG
authors.lastname: Sierra
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Asakawa
authors.forename: Alicia
authors.initials: A
authors.lastname: Bardón
mesh_terms: D000818:Animals; D019659:Asteraceae / Q000737:chemistry*; D018360:Crystallography, X-Ray; D005247:Feeding Behavior / Q000187:drug effects*; D007814:Larva / Q000187:drug effects; D015394:Molecular Structure; D035261:Plant Components, Aerial / Q000737:chemistry; D028321:Plant Preparations / Q000737:chemistry / Q000494:pharmacology*; D012717:Sesquiterpenes / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D045787:Sesquiterpenes, Eudesmane / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D018411:Spodoptera / Q000187:drug effects*
chemical_list: C531204:3alpha-(2,3-epoxy-2-methylbutyryloxy)-4alpha-formoxy-11-hydroxy-6,7-dehydroeudesman-8-one; D028321:Plant Preparations; D012717:Sesquiterpenes; D045787:Sesquiterpenes, Eudesmane; C015872:eudesmane