反应详情

To a mixture of 3-(2,3,4,6-tetra-O-benzyl-β-D-glucopyranosyl)-1-[4-((1E)-3-carboxyprop-1-enyl)benzyl]-7-methyl-1H-indole (0.30 g), (R)-(−)-2,2-dimethyl-1,3-dioxolane-4-methanol (62 mg), 4-dimethylaminopyridine (22 mg) and dichloromethane (1 mL) was added dicyclohexylcarbodiimide (0.11 g), and the mixture was stirred at room temperature overnight. The reaction mixture was directly purified by column chromatography on silica gel (eluent: n-hexane/ethyl acetate=3/1-3/2) to give 3-(2,3,4,6-tetra-O-benzyl-β-D-gluco-pyranosyl)-1-(4-{(1E)-3-[((S)-2,2-dimethyl-1,3-dioxolan-4-yl)methoxycarbonyl]prop-1-enyl}benzyl)-7-methyl-1H-indole (0.23 g). To a suspension of this material in dichloromethane (2 mL)-methanol (4 mL) was added Amberlyst 15 (0.40 g), and the mixture was stirred at 50° C. for 4 hours. The insoluble material was removed by filtration, and the solvent was removed under reduced pressure. The residue was purified by column chromatography on silica gel (eluent: n-hexane/ethyl acetate=1/2-1/4) to give 3-(2,3,4,6-tetra-O-benzyl-β-D-gluco-pyranosyl)-1-{4-[(1E)-3-((S)-2,3-dihydroxypropoxycarbonyl)-prop-1-enyl]benzyl}-7-methyl-1H-indole (0.12 g). This material was dissolved in a mixed solvent of methanol (2 mL) and tetra hydrofuran (2 mL). To the solution was added 10% palladium-carbon powder (0.10 g), and the mixture was stirred at room temperature under a hydrogen atmosphere for 4 hours. The insoluble material was removed by filtration, and the solvent was removed under reduced pressure. The residue was purified by column chromatography on silica gel (eluent: dichloromethane/methanol=8/1-5/1) to give the title compound (58 mg).

1. customThe reaction mixture was directly purified by column chromatography on silica gel (eluent: n-hexane/ethyl acetate=3/1-3/2)