反応 #554621

反応方程式

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

収率 80.0%

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

収率 80.0%

溶媒

pyridine

反応条件

後処理

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

実験手順

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.

出典