Novel Glycosidic Constituents from Saffron

Abstract

The methanolic extract of saffron was prefractionated with the aid of multilayer coil countercurrent chromatography (MLCCC). After subsequent purification of certain fractions by high-performance liquid chromatography, the following glycoconjugates were isolated and identified on the basis of their spectral (UV, MS, NMR) data: the β-d-glucosides of (4R)-4-hydroxy-3,5,5-trimethylcyclohex-2-enone (5), (4S)-4-hydroxy-3,5,5-trimethylcyclohex-2-enone (6), and (4S)-4-(hydroxymethyl)-3,5,5-trimethylcyclohex-2-enone (7), as well as the β-d-gentiobiosyl ester of 2-methyl-6-oxohepta-2,4-dienoic acid (4). In addition to these new natural products, known saffron constituents, i.e., the di-β-d-gentiobiosyl and β-d-gentiobiosyl-β-d-glucopyranosyl esters of crocetin, have also been isolated and separated using MLCCC. Keywords: (4R)-4-Hydroxy-3,5,5-trimethylcyclohex-2-enone 4-O-β-d-glucopyranoside; (4S)-4-hydroxy-3,5,5-trimethylcyclohex-2-enone 4-O-β-d-glucopyranoside; (4S)-4-(hydroxymethyl)-3,5,5-trimethylcyclohex-2-en...