Mass spectrometric methods for the analysis of chlorinated and nitrated isoflavonoids: a novel class of biological metabolites.
Electrospray ionization combined with tandem mass spectrometry was applied to a study of some representative chlorinated and nitrated isoflavones-potential metabolites of isoflavones in inflammatory cells. Upon collision-induced dissociation of deprotonated [M - H](-) ions of these compounds, a number of structurally characteristic product ions were produced. The product ion analysis of 3'- and 8-chlorodaidzein in the tandom mass spectra led to ready differentiation of these isomers. 3-Nitro derivatives of both genistein and daidzein have product ions due to the losses of HNO(2) and two OH groups. Chlorinated derivatives of isoflavones were detected in cell-based experiments and their structures were proposed by comparing the tandem mass spectra of their product ions with those of standards. This work provides a suitable analytical basis to aid the characterization of chlorinated and nitrated metabolites in studies in vivo and in vitro.
Prasain
Jeevan K
JK
Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA.
Patel
Rakesh
R
Kirk
Marion
M
Wilson
Landon
L
Botting
Nigel
N
Darley-Usmar
Victor M
VM
Barnes
Stephen
S
D002713:Chlorine / Q000737:chemistry / Q000378:metabolism; D019833:Genistein / Q000032:analysis / Q000378:metabolism; D018922:HL-60 Cells; D006801:Humans; D007529:Isoflavones / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D009566:Nitrates / Q000737:chemistry / Q000378:metabolism; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
D007529:Isoflavones; D009566:Nitrates; C040641:genistin; D002713:Chlorine; C004742:daidzein; D019833:Genistein; C004541:biochanin A