反应详情

To a solution of 3-cyclopropylmethyl-8-[4-aminobenzyl]-1-(2-fluorobenzyl)-3,7-dihydro-purine-2,6-dione (0.21 g, 0.50 mmol) in tetrahydrofuran (tetrahydrofuran) (5 mL) was added acetone (36.7 μL, 5.0 mmol) and sodium cyanoborohydride (Aldrich, catalog number 15,615-9) (94.3 mg, 1.5 mmol). Stirred vigorously at ambient temperature and glacial acetic acid (J. T. Baker, catalog number 9508-5) (50 μL, 0.87 mmol) added. After 3 h additional glacial acetic acid (50 μL, 0.87 mmol) was added and the mixture stirred at ambient temperature for an additional 1 h. The reaction mixture was diluted with dichloromethane and washed with 1M aqueous sodium hydroxide (2×), brine, dried (sodium sulfate) and concentrated in vacuo. The residue was purified by chromatography using silica eluted with 1:2 hexanes/ethyl acetate. Concentration of the appropriate fractions gave the product as a colorless solid (0.055 g, 23%). 1H NMR, δH(DMSO-d6, 300 MHz) 13.29 (br s, 1H), 7.30–6.85 (m, 6H), 6.40 (d, J=8.8 Hz, 2H), 5.16 (d, J=8.4 Hz, 1H), 5.04 (s, 2H), 3.78 (s, 2H), 3.42 (sept, J=6.4 Hz, 1H), 1.25–1.10 (m, 1H), 1.01 (d, J=6.2 Hz, 6H) and 0.45–0.30 (m, 4H)

1. stirringthe mixture stirred at ambient temperature for an additional 1 h
2. washwashed with 1M aqueous sodium hydroxide (2×), brine
3. dry with materialdried (sodium sulfate)
4. concentrationconcentrated in vacuo
5. customThe residue was purified by chromatography
6. washeluted with 1:2 hexanes/ethyl acetate