HPLC analyses of dry extracts obtained from Passiflora incarnata revealed the presence of ten known flavonoids whose structures were characterised by ionspray ioni-zation tandem mass spectrometry; in addition, three unidentified peaks, F1, 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-β-D-glucopyranosyl-8-β-D-ribopyranosyl apigenin to the new di-C-glycosylflavonoid F2.
mass spectrometry, C-glycosylflavonoids, Passiflora incarnata L., H-1-NMR, C-13-NMR
Publication DOI: 10.1080/10575639808044951Journal NLM ID: 9315615Publisher: Taylor & Francis Health Sciences
Institutions: Centro CNR sulla Chimica e la Struttura dei Composti Eterociclici e Dipartimento di Chimica Organica dell’Università, Firenze, Italy, Aboca S.S., Sansepolcro, Italy, CISM, Universita di Firenze, Firenze, Italy, Dipartimento di Chimica, Universith di Pisa, Pisa, Italy
Methods: 13C NMR, 1H NMR, TLC, HPLC, extraction, CC, DQF-COSY, HMBC, HMQC, CF-FAB-MS, ISI-MS-MS
Found