121063-56-7

2,5-Dimethyl-4-hydroxy-3-(2H)furanone β-glucoside has been isolated from strawberry juice and synthesized.Both the natural and synthetic material exist as a diastereoisomers. - Keywords: Fragaria ananassa; Rosaceae; glucoside; 2,5-dimethyl-4-hydroxy-3(2H)-furanone glucoside.

2,5-Dimethyl-4-hydroxy 3[2H]-furanone 6'-O-malonyl-β-D-glucopyranoside was isolated from a glycosidic extract of strawberry fruit (Fragaria X ananassa, cv. Senga Sengana) by means of countercurrent chromatography and reverse-phase HPLC. Identification was achieved by comparison of chromatographic and 1H, 13C and 2D-NMR, as well as mass spectral data with those of the synthesized reference compound. In ripe strawberry fruit, a 1:1 ratio of the malonylated glucoside to its deacylated glucoconjugate was determined by on-line liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry.

Various conditions for glycosylation (Koenigs-Knorr, Helferich, trichloroacetimidate, Fischer-Raske, phase-transfer methods) of 3-ethoxy-4-hydroxybenzaldehyde (ethyl vanillin), 3-hydroxy-2-methyl-4-pyranone (maltol) and 2,5-dimethyl-4-hydroxy-3(2H)-furanone (furaneol(R)) were evaluated, taking into account yields and ease of preparation (e.g., utilized donor, catalyst, conditions). The best results were achieved employing phase transfer catalysis in a two-phase solvent mixture. To increase water solubility for better applicability, the hitherto unknown maltosides of the corresponding alcohols were synthesized, again proving the value of phase-transfer conditions for glycosylation of phenols.