Water → 4-benzyl-1-ethoxycarbonyl-5-isopropyl-3-(2,3,4,6-tetra-O-pivaloyl-beta-D-glucopyranosyl-oxy)-1H-pyrazole

Participants

Reaction Steps

To a solution of 4-benzyl-1-ethoxycarbonyl-1,2-dihydro-5-isopropyl-3H-pyrazol-3-one (0.100 g) in acetonitrile (3 mL) were added potassium carbonate (0.0575 g) and 2,3,4,6-tetra-O-pivaloyl-α-D-glucopyranosyl bromide (0.211 g) successively under stirring at room temperature. In addition, the mixture was stirred at 50° C. for 2.5 hours. The mixture was poured into water, and the resulting mixture was extracted with diethyl ether. The organic layer was washed with brine and dried over anhydrous magnesium sulfate. The insoluble materials were removed by filtration, and the filtrate was concentrated under reduced pressure. The residue was purified by column chromatography on silica gel (eluent: ethyl acetate/n-hexane=1/8 to 1/5 to 1/4) to give 4-benzyl-1-ethoxycarbonyl-5-isopropyl-3-(2,3,4,6-tetra-O-pivaloyl-β-D-glucopyranosyloxy)-1H-pyrazole (0.15 g).

Provenance & Evidence