title: Triple quadrupole tandem mass spectrometry of sesquiterpene lactones: a study of goyazensolide and its congeners.
abstract: Electrospray ionization tandem mass spectrometry (ESI-MS/MS) was used to investigate the fragmentation pattern of ten sesquiterpene lactones of the goyazensolide type under low-energy collision-induced dissociation (CID) using a triple quadrupole mass spectrometer. The analysis revealed that loss of CO(2)[M + H - 44](+) is the predominant process for compounds that exhibit a hydroxyl at C-8. In contrast, compounds with different acyloxy groups at C-8 fragment by means of elimination of the corresponding carboxylic acids [M + H - (R(2)CO(2)H)](+) and consecutive losses of CO and H(2)O. Our results also demonstrate the influence of both the stereochemistry of the acyloxy group at C-8 on the relative abundances of product ions and the hydroxyl at C-15, which creates an additional pathway, resulting in highly diagnostic product ions. This work clearly demonstrates the utility of tandem quadrupole low-resolution mass spectrometry for studies on the rationalization of the fragmentation of a series of compounds with a highly conserved core structure, but differing in substituent groups.
authors.affiliation: Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Antônio E M
authors.initials: AE
authors.lastname: Crotti
authors.forename: João L C
authors.initials: JL
authors.lastname: Lopes
authors.forename: Norberto P
authors.initials: NP
authors.lastname: Lopes
mesh_terms: D019659:Asteraceae / Q000737:chemistry; D001952:Bridged-Ring Compounds / Q000737:chemistry*; D005663:Furans / Q000737:chemistry*; D013058:Mass Spectrometry / Q000379:methods*; D012717:Sesquiterpenes / Q000737:chemistry*; D054830:Sesterterpenes
chemical_list: D001952:Bridged-Ring Compounds; D005663:Furans; D012717:Sesquiterpenes; D054830:Sesterterpenes; C499803:furanoheliangolide