To a solution of 4-[(4-ethylthiophenyl)methyl]-3-(β-D-glucopyranosyloxy)-5-methyl-1H-pyrazole (0.41 g) in tetra-hydrofuran (10 mL) were added acetic acid (0.11 mL) and acetic anhydride (0.18 mL), and the mixture was stirred at room temperature overnight. The reaction mixture was concentrated under reduced pressure, and diethyl ether was added to the residue. The resulting precipitated crystal was collected by filtration to give 1-acetyl-4-[(4-ethylthiophenyl)methyl]-3-(β-D-glucopyranosyloxy)-5-methylpyrazole (0.36 g).
