The Mass Spectra of Chalcones, Flavones and Isoflavones

The fragmentation of flavonoid compounds by electron impact has been studied and the following results described: 1) Chalcones gave the usual fragmentation pattern; however, 2′-hydroxy chalcones showed complex spectra according to the isomerization of chalcone to flavanone. 2) The fragmentation pathways of flavones were decided by comparison with many kinds of halogen-substituted flavones. 3) Isoflavone gave the M-1 ion as the base peak, and no loss of CO was observed.