To a suspension of 3-(β-D-glucopyranosyloxy)-4-[(4-isopropoxyphenyl)methyl]-5-methyl-1H-pyrazole (50 mg) and cesium carbonate (0.20 g) in N,N-dimethylformamide (1 mL) was added 1-iodopropane (0.036 mL) at 50° C., and the mixture was stirred overnight. Water was added to the reaction mixture, and the resulting mixture was purified by solid phase extraction on ODS (washing solvent: distilled water, eluent: methanol). The resulting semi-purified material was purified by column chromatography on silica gel (eluent: dichloromethane/methanol=8/1) to give 3-(β-D-glucopyranosyloxy)-4-[(4-isopropoxyphenyl)methyl]-5-methyl-1-propylpyrazole (28 mg).
