3-HYDROXY-5,6-EPOXY-BETA-IONOL BETA-D-GLUCOPYRANOSIDE AND 3-HYDROXY-7,8-DIHYDRO-BETA-IONOL BETA-D-GLUCOPYRANOSIDE - NEW C-13 NORISOPRENOID GLUCOCONJUGATES FROM SLOE TREE (PRUNUS-SPINOSA L) LEAVES

After isolation of a glycosidic extract obtained from sloe tree (Prunus spinosa L.) leaves by Amberlite XAD-2 adsorption and methanol elution followed by hydrolysis with a commercial pectinase enzyme, HRGC and HRGC-MS analyses revealed the occurrence of 41 aglycons. Benzaldehyde, benzyl alcohol, and benzoic acid were found as major constituents. In addition, a number Of C-13 norisoprenoids, i.e. isomeric oxoactinidols, 3-hydroxy-7,8-dehydro-beta-ionone, 3-oxo-alpha-ionol, 3-hydroxy-7,8-dihydro-beta-ionol, 3-hydroxy-5,6-epoxy-beta-ionol, 3-hydroxy-beta-ionone, and vomifoliol were also present in the milligram per kilogram range. By using prefractionation of the glycosidic leaf extract by rotation locular counter-current chromatography (RLCC), subsequent acetylation and liquid chromatographic purification, two glycoconjugates were isolated in pure form whose structures were elucidated by LC-MS and NMR analyses to be beta-D-glucopyranosides of 3-hydroxy-5,6-epoxy-beta-ionol and 3-hydroxy-7,8-dihydro-beta-ionol, respectively.