The occurrence in olive oil of a new class of phenolic compounds: hydroxy-isochromans

A new class of phenolic compounds, hydroxy-isochromans, was found in different samples of extra-virgin olive oil. In particular, the presence of 1-phenyl-6,7-dihydroxy-isochroman, 10 and 1-(3'-methoxy-4'-hydroxy)phenyl-6,7-dihydroxy-isochroman, 11 was demonstrated by comparison of the high performance liquid chromatography-mass/mass (HPLC-MS/MS) spectra of biophenolic samples from extra-virgin olive oils with those of compounds obtained by a reaction between hydroxytyrosol and the aromatic aldehydes, benzaldehyde and vanillin, respectively. (C) 2002 Published by Elsevier Science Ltd.