反应详情

3′-O-[(tertbutyl)dimethylsilyl]-5′-O-[(tertbutyl)diphenylsilyl]-4′-C-(1,1′-diphenylmethylaminomethyl)thymidine (2) (1.2 g, 1.5 mmol) was dissolved in tetrahydrofuran (50 mL) at ambient temperature. A solution of tetrabutylammonium fluoride in tetrahydrofuran (4.5 mL) was then added to the solution. The resulting mixture was stirred for 3 hours at ambient temperature. Methanol (5 mL) was then added and the reaction mixture concentrated under vacuum. The residue was purified by flash column chromatography (95:5 dichloromethane:methanol) to give the title compound (3) as an amorphous white solid (0.65 g, 100%) on removal of solvent from the appropriate fractions. δH(300 MHz, d6-DMSO) 11.23(1H, s, br, N3—H), 7.75(1H, s, H-6), 7.41–7.15(10H, m, Ph2CHNH), 6.21(1H, dd, H-1′), 5.57(1H, d, br, 3′-OH), 5.21(1H, t, 5′-OH), 4.78(1H, s, Ph2CHNH), 4.35(1H, m, H-3′), 3.61(2H, 2d, H-5′), 2.54(2H, 2d, 4′-C—CH2), 2.18(2H, m, H-2′), 1.75(3H, s, 5-CH3); δC(75.45 MHz, d6-DMSO) 150.46, 144.53, 144.28, 136.28, 128.36, 126.99, 126.74, 109.17, 88.39, 83.18, 66.79, 64.10, 54.91, 12.27.

1. concentrationthe reaction mixture concentrated under vacuum
2. customThe residue was purified by flash column chromatography (95:5 dichloromethane:methanol)