HPLC analyses of dry extracts obtained from Passiflora incamata revealed the presence of ten known flavonoids whose structures were characterised by ionspray ionization tandem mass spectrometry; in addition, three unidentified peaks, F l, F2, and F3 appeared in the flavonoid region of the chromatogram. Two components were detected in F3 by on-line HPLC-ISI-MS analysis, named F3a and! F3b. F2 was demonstrated to be a structural isomer of schaftoside (1 ), and F3a of isoschaftoside (2), with apigenin as the common aglycone and molecular weight 564. Mass spectra and 2D-NMR experiments allowed us to assign the structure of 6-J3-D-glucopyranosyl-8-J3-D-ribopyranosyl apigenin to the new di-C-glycosylflavonoid F2.
Isolation and Characterization of an Unknown Flavonoid in Dry Extracts from Passiflora Incarnata
Andrea Raffaelli;
1998
Abstract
HPLC analyses of dry extracts obtained from Passiflora incamata revealed the presence of ten known flavonoids whose structures were characterised by ionspray ionization tandem mass spectrometry; in addition, three unidentified peaks, F l, F2, and F3 appeared in the flavonoid region of the chromatogram. Two components were detected in F3 by on-line HPLC-ISI-MS analysis, named F3a and! F3b. F2 was demonstrated to be a structural isomer of schaftoside (1 ), and F3a of isoschaftoside (2), with apigenin as the common aglycone and molecular weight 564. Mass spectra and 2D-NMR experiments allowed us to assign the structure of 6-J3-D-glucopyranosyl-8-J3-D-ribopyranosyl apigenin to the new di-C-glycosylflavonoid F2.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
