Cesium carbonate → 4-[(4-ethylphenyl)methyl]-3-(beta-D-glucopyranosyloxy)-1-(3-hydroxypropyl)-5-methyl-1H-pyrazole

Participants

Reaction Conditions

Reaction Steps

To a suspension of 4-[(4-ethylphenyl)methyl]-5-methyl-3-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyloxy)-1H-pyrazole (0.030 g) and cesium carbonate (0.091 g) in acetonitrile (0.4 mL) was added benzyl(3-bromopropyl)ether (0.039 mL), and the mixture was stirred at 80° C. for 30 minutes. To the reaction mixture were added methanol (0.4 mL) and 2 mol/L aqueous sodium hydroxide solution (0.55 mL), and the mixture was stirred at room temperature overnight. Water was added to the reaction mixture, and the mixture was purified by solid phase extraction on ODS (washing solvent: distilled water, eluent: methanol). To the resulting eluent was added a catalytic amount of 10% palladium-carbon powder, and the mixture was stirred at room temperature under a hydrogen atmosphere for 3 days. Insoluble materials were removed by filtration, and the solvent of the filtrate was removed under reduced pressure. The residue was purified by liquid chromatography on ODS (eluent: methanol/water=40/60) to give 4-[(4-ethylphenyl)methyl]-3-(β-D-glucopyranosyloxy)-1-(3-hydroxypropyl)-5-methyl-1H-pyrazole (0.0080 g).

Provenance & Evidence