Characterization of acylated flavonoid‐ O ‐glycosides and methoxylated flavonoids from Tagetes maxima by liquid chromatography coupled to electrospray ionization tandem mass spectrometry

Liquid chromatography coupled to negative electrospray ionization (ESI) tandem mass spectrometry (MS/MS) employing a triple quadrupole mass spectrometer was used in the structural determination of acylated flavonoid‐ O ‐glycosides and methoxylated flavonoids occurring in Tagetes maxima . The compounds were identified by experiments in full scan mode (MS), and tandem mass experiments (MS/MS) of precursor ion scan, product ion scan, and neutral loss scan modes. In order to characterize the aglycones of the flavonoid glycosides, in‐source fragmentation of the deprotonated molecule [MH] − followed by product ion scan of the resulting aglycone [AH] − were performed. This combined approach allowed the identification of 51 phenolic compounds, including flavonoid‐ O ‐glycosides acylated with galloyl, protocatechuoyl, coumaroyl or caffeoyl groups, methoxylated flavonoids, and hydroxycinnamic acid and phenolic acid derivatives, none of them previously reported in Tagetes maxima . Copyright © 2004 John Wiley & Sons, Ltd.