反应详情

(R)-9-[2-Hydroxymethyl 4-(t-butyldiphenylsilyloxy)butyl]guanine (2.31 g, 5 mmole) was coevaporated with dry pyridine twice and dissolved in pyridine (20 ml). To the solution was slowly added dropwise stearoyl chloride (1.86 ml, 5.5 mmole, technical grade) in dichloromethane (2 ml) at −5° C. The reaction was kept at the same temperature for 1 hr and then at 5° C. for 2 hr. The reaction was monitored by TLC. Additional stearoyl chloride (0.29 ml) at −5° C. was added due to incompletion of reaction. After 30 min at 5° C., methanol (3 ml) was added and the reaction mixture stirred for 20 min. It was then poured into aqueous sodium hydrogen carbonate solution, and extracted with dichloromethane. The organic phase was dried and the product purified by silica gel column chromatography with stepwise increasing MeOH, eluting with 3.5% MeOH in CH2Cl2. (Yield 2.7 g).

1. waitat 5° C. for 2 hr
2. waitAfter 30 min at 5° C.
3. extractionextracted with dichloromethane
4. customThe organic phase was dried
5. customthe product purified by silica gel column chromatography with stepwise increasing MeOH
6. washeluting with 3.5% MeOH in CH2Cl2