title: [Mass spectrum characterization of five valepotriates by electrospray ionization tandem mass spectrometry].
abstract: OBJECTIVE
  To discuss mass spectrum characterization of five valepotriates including 'monoene' type (didrovaltrate), 'diene' type (valtrate, acevaltrate) and 'four-olefinic' type (baldrinal and homobaldrinal) by electrospray ionization tandem mass spectrometry (ESI-MS(n)).
  
  
  METHODS
  This study was carried out on the basis of electrospray ionization tandem mass spectrometric method and analysis of multistage fragments.
  
  
  RESULTS
  The fragmentation patterns and structural assignment of 'monoene' type, 'diene' type and 'four-olefinic' type valepotriates in ESI-MSn under positive mode were summarized.
  
  
  CONCLUSIONS
  The compounds have a strong pyrolysis rules and it can provide reference date for valepotriates in rapid structural identification, quantitative analysis and pharmacokinetic study.
authors.affiliation: Beijing University of Chinese Medicine, Beijing 100029, China.
authors.forename: Chun-Guo
authors.initials: CG
authors.lastname: Wang
authors.forename: Yong
authors.initials: Y
authors.lastname: Liu
authors.forename: Jin-Li
authors.initials: JL
authors.lastname: Shi
authors.forename: Yao
authors.initials: Y
authors.lastname: Xiao
authors.forename: Shu-Ning
authors.initials: SN
authors.lastname: Shi
authors.forename: Wen-Hui
authors.initials: WH
authors.lastname: Hou
authors.forename: Zi-Jian
authors.initials: ZJ
authors.lastname: Wang
mesh_terms: D004365:Drugs, Chinese Herbal / Q000737:chemistry*; D039823:Iridoids / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry
chemical_list: D004365:Drugs, Chinese Herbal; D039823:Iridoids; C009643:valtrates (combination)