反应详情

温度

70 °C

To a suspension of 5-amino-3,6-dihydrothiazolo[4,5-d]pyrimidine-2,7-dione (186 mg, 1 mmol) in ACN (10 mL) was added BSA (630 mg, 3 mmol). The resulting reaction mixture was then stirred at 70° C. under argon for 0.5 hour to form a clear solution. After the solution was cooled to room temperature, 1-[(2S,4R)-4-azido-5-methoxy-tetrahydrofuran-2-yl]ethyl benzoate (compound 25k, 300 mg, 1.0 mmol) and TMSOTf (1.15 g, 5 mmol) were added in sequence. After being heated at 70° C. for 14 hours, the solvent was removed in vacuo. The residue was partitioned between EtOAc and saturated NaHCO3 solution (30 mL). The organic layer was separated and the aqueous phase was extracted with EtOAc (30 mL) twice. The combined organic layers were washed with brine, dried over Na2SO4 and concentrated in vacuo to afford 600 mg crude product of 1-[(2S,4R,5R)-5-(5-amino-2,7-dioxo-6H-thiazolo[4,5-d]pyrimidin-3-yl)-4-azido-tetrahydrofuran-2-yl]ethyl benzoate (compound 25l), which was used in next step without further purification. MS obsd. (ESI+) [(M+H)+]: 442.

1. additionwas added BSA (630 mg, 3 mmol)
2. customThe resulting reaction mixture
3. customto form a clear solution
4. temperatureAfter the solution was cooled to room temperature
5. temperatureAfter being heated at 70° C. for 14 hours
6. customthe solvent was removed in vacuo
7. customThe residue was partitioned between EtOAc and saturated NaHCO3 solution (30 mL)
8. customThe organic layer was separated
9. extractionthe aqueous phase was extracted with EtOAc (30 mL) twice
10. washThe combined organic layers were washed with brine
11. dry with materialdried over Na2SO4
12. concentrationconcentrated in vacuo