To a solution of 4-[(4-hydroxy-2-methylphenyl)methyl]-5-isopropyl-3-(2,3,4,6-tetra-O-pivaloyl-β-D-glucopyranosyloxy)-1H-pyrazole (0.4 g), 3-[N-benzyloxycarbonyl-N-(3-bromopropyl)amino]propionamide (0.28 g) and tetra(n-butyl)ammonium bromide (87 mg) in dichloromethane (4 mL) was added 5 mol/L aqueous sodium hydroxide solution (0.32 mL), and the mixture was stirred at room temperature overnight. The reaction mixture was poured into 1 mol/L hydrochloric acid, and the resulting mixture was extracted with diethylether. The extract was washed with 1 mol/L hydrochloric acid, water and brine, and dried over anhydrous magnesium sulfate. The solvent was removed under reduced pressure, and the residue was purified by column chromatography on silica gel (eluent: n-hexane/ethyl acetate=1/3-1/6) to give the title compound (0.42 g).
