反应详情

A mixed solution of 5-bromo-2-chloro-1-(tert-butyldiphenylsilyloxymethyl)benzene 77 (10.83 g) and 2,3,4,6-tetrakis-O-trimethylsilyl-D-glucono-1,5-lactone 2 (see U.S. Pat. No. 6,515,117) (13.2 g) in tetrahydrofuran (400 ml) was cooled to −78° C. under argon atmosphere, and thereto was added dropwise tert-butyl lithium (1.60 M pentane solution, 30.9 ml), and the mixture was stirred at the same temperature for 30 minutes to give a compound 78. Without isolating this compound, a solution of methanesulfonic acid (6.12 ml) in methanol (200 ml) was added to the reaction solution, and the reaction mixture was warmed to room temperature, and stirred at the same temperature for 15 hours. Under ice-cooling, to the mixture was added a saturated aqueous sodium hydrogen carbonate solution, and the mixture was extracted with ethyl acetate. The extract was washed with brine, and dried over magnesium sulfate. The solvent was evaporated under reduced pressure, and the residue was purified by silica gel column chromatography (chloroform:methanol=93:7) to give a methyl ether compound 79 (9.71 g) as colorless powder. APCI-Mass m/Z 590/592 (m+NH4). (2) A solution of the above methyl ether compound 79 (3.46 g) in dichloromethane (70 ml) was cooled to 0° C. under argon atmosphere, and thereto were added dropwise successively triethylsilane (2.89 ml) and boron trifluoride•diethyl ether complex (2.28 ml). The mixture was stirred at the same temperature for 1 hour. Under ice-cooling, a saturated aqueous sodium hydrogen carbonate solution was added, and the mixture was extracted with ethyl acetate. The extract was washed with brine and dried over magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (chloroform:methanol=100:0-94:4) to give 1-(β-D-glucopyranosyl)-4-chloro-3-(tert-butyldiphenylsilyloxymethyl)benzene 80 (2.52 g) as colorless powder. APCI-Mass m/Z 560/562 (M+NH4). (3) The above compound 80 (4.12 g) was treated in a manner similar to Example 106-(1) to give the compound 81 (5.44 g). APCI-Mass m/Z 728/730 (M+NH4). (4) A mixed solution of the above compound 81 (5.44 g), acetic acid (1.29 ml) in tetrahydrofuran (60 ml) was cooled to 0° C. under argon atmosphere, and thereto was added tetrabutyl ammonium fluoride (1.0 M tetrahydrofuran solution, 8.43 ml). The mixture was stirred at the same temperature for 30 minutes, and then further stirred at room temperature for 15 hours. The mixture was diluted with ethyl acetate and washed successively with 0.4 M aqueous hydrochloric acid solution, a saturated aqueous sodium hydrogen carbonate solution and brine. The mixture was dried over magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane:ethyl acetate=4:1-1:1) to give the compound 82 (2.97 g) as a colorless solid. APCI-Mass m/Z 490/492 (M+NH4). (5) A solution of the above compound 82 (1.60 g) in dichloromethane (50 ml) was cooled to 0° C. under argon atmosphere, and thereto was added Dess-Martin periodinane (1.58 g). The mixture was warmed to room temperature and stirred at the same temperature for 3 hours. The mixture was diluted with ethyl acetate, and insoluble materials were filtered off. The filtrate was washed successively with a saturated aqueous sodium hydrogen carbonate solution and brine, and dried over magnesium sulfate. The solvent was evaporated under reduced pressure, and the residue was purified by silica gel column chromatography (hexane:ethyl acetate=3:1-1:1) to give 5-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl)-2-chloro benzaldehyde 83 (1.35 g) as colorless crystals. APCI-Mass m/Z 488/490 (M+NH4). (6) To a mixed solution of the above 5-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl)-2-chlorobenzaldehyde 83 (325 mg), 2,3-dihydro-1H-isoindole (98 mg), acetic acid (82 mg) in 1,2-dichloroethane (5 ml) was added sodium triacetoxyborohydride (219 mg). The mixture was stirred at room temperature for 3 hours, and cooled to 0° C. A saturated aqueous sodium hydrogen carbonate solution was added thereto to basify the reaction mixture. The mixture was extracted with ethyl acetate, and the extract was washed with brine, and dried over magnesium sulfate. The solvent was evaporated under reduced pressure, and the residue was purified by silica gel column chromatography (hexane:ethyl acetate=1:0-1:1) to give 1-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl)-4-chloro-3-(1,3-dihydro-isoindol-2-ylmethyl)benzene 84 (234 mg) as a colorless solid. APCI-Mass m/Z 574/576 (M+H). (7) The above 1-(2,3,4,6-tetra-O-acetyl-β-Dglucopyranosyl)-4-chloro-3-(1,3-dihydro-isoindol-2-ylmethyl)benzene 84 was treated in a manner similar to Example 106-(3) to give the desired 1-(β-D-glucopyranosyl)-4-chloro-3-(1,3-dihydro-isoindol-2-ylmethyl)benzene 85 as colorless powder. APCI-Mass m/Z 406/408 (M+H).

1. temperaturecooled to 0° C
2. extractionThe mixture was extracted with ethyl acetate
3. washthe extract was washed with brine
4. dry with materialdried over magnesium sulfate
5. customThe solvent was evaporated under reduced pressure
6. customthe residue was purified by silica gel column chromatography (hexane:ethyl acetate=1:0-1:1)