反应 #533870

反应方程式

N2-isobutyryl-3′-O-(methylthimethyl)-5′-O-(tert-butyldimethylsilyl)-2′-deoxyguanosine

N2-isobutyryl-3′-O-(methylthiomethyl)-5′-O-(tert-butyldimethylsilyl)-2′-deoxyguanosine

diphenylcarbamoyl chloride

N,N-diisopropylethylamine

→

product 12

收率 80.0%

N2-isobutyryl-O6-diphenylcarbamoyl-3′-O-(methylthiomethyl)-5′-O-(tert-butyldimethylsilyl)-2′-deoxyguanosine

收率 80.0%

溶剂

pyridine

反应条件

后处理

1. 1
   其他The solvent was removed under high vacuum, and product
2. 2
   其他was then purified by silica gel column chromatography

实验过程

To 1.0 g N2-isobutyryl-3′-O-(methylthimethyl)-5′-O-(tert-butyldimethylsilyl)-2′-deoxyguanosine (11, 1.95 mmol) dissolved in 22 mL dry pyridine were added diphenylcarbamoyl chloride (0.677 g, 2.92 mmol) and 1.02 mL N,N-diisopropylethylamine, and stirred at room temperature for 3 h under nitrogen atmosphere. The reaction mixture became dark red during this time. The solvent was removed under high vacuum, and product was then purified by silica gel column chromatography using EtOAc:hex/1:1 to 7:3 as mobile phase. The product 12 was isolated as yellowish powder (1.09 g, ˜80% yield; Rf=0.7, EtOAc:hex (1:1)). HR-MS: Obs. m/z 707.3068 calcd. for C35H47O6N6SiS 707.3047 [M+H]+. 1H-NMR (CDCl3): δH 8.25 (s, 1H), 7.94 (brs, 1H), 7.47-7.37 (m, 10H), 6.42 (m, 1H), 4.75 (m, 2H), 4.71 (m, 1H), 4.18 (m, 1H), 3.88-3.70 (m, 2H), 2.80 (m, 1H), 2.60 (m, 1H), 2.19 (s, 3H), 1.30 (d, J=7.2 Hz, 6H), 0.93 (s, 9H) and 0.14 (s, 6H) ppm.

来源