反应 #554617

反应方程式

NaHCO3

N6-Benzoyl-5′-O-tert-butyldimethylsilyl-2′-deoxyadenosine

DMSO

acetic anhydride

→

N6-benzoyl-3′-O -(methylthiomethyl)-5′-O-(tert-butyldimethylsilyl)-2′-deoxyadenosine

收率 71.0%

N6-Benzoyl-3′-O-(methylthiomethyl)-5′-O-(tert-butyldimethylsilyl)-2′-deoxyadenosine

收率 71.0%

溶剂

acetic acid

反应条件

后处理

1. 1
   萃取extracted with CH2Cl2 (3×100 mL)
2. 2
   萃取The combined organic extract
3. 3
   洗涤was then washed with a saturated NaHCO3 solution (100 mL)
4. 4
   干燥dried over Na2SO4
5. 5
   浓缩concentrated under vacuum
6. 6
   其他The resultant yellowish oil was then purified on silica gel column (Hex: EtOAc/1:1 to 1:4)

实验过程

3.0 g N6-Benzoyl-5′-O-tert-butyldimethylsilyl-2′-deoxyadenosine (5a) (6.38 mmol) was dissolved in a mixture consisting of 11.96 mL DMSO, 5.46 mL acetic acid, and 17.55 mL acetic anhydride and stirred at room temperature for 48 h. The reaction mixture was then neutralized treating with a sufficient amount of saturated NaHCO3 solution and extracted with CH2Cl2 (3×100 mL). The combined organic extract was then washed with a saturated NaHCO3 solution (100 mL), dried over Na2SO4, and concentrated under vacuum. The resultant yellowish oil was then purified on silica gel column (Hex: EtOAc/1:1 to 1:4) to obtain the product N6-benzoyl-3′-O -(methylthiomethyl)-5′-O-(tert-butyldimethylsilyl)-2′-deoxyadenosine (6a) as white powder in 71% yield (2.4 g, Rf 0.6, EtOAc: hex/7:3). HR-MS: obs. m/z 530.2273, calcd. for C25H36O4N5SiS 530.2257 [M+H]+. 1H-NMR (CDCl3): δH 9.00 (s, 1H), 8.83 (s, 1H), 8.35 (s, 1H), 8.05 (d, J=7.6 Hz, 2H), 7.62 (m, 1H), 7.55 (m, 2H), 6.55 (t, J=7.19 Hz, 1H), 4.73 (m, 2H), 4.68 (m, 1H), 4.24 (m, 1H), 3.88 (dd, J=11.19, 3.19 Hz, 1H), 2.74-2.66 (m, 2H), 2.35 (s, 3H), 0.94 (s, 9H) and 0.13 (s, 6H) ppm.

来源