반응 #89031

반응 방정식

5-amino-3,6-dihydrothiazolo[4,5-d]pyrimidine-2,7-dione

[(2S,4R,5R)-4-azido-5-methoxy-tetrahydrofuran-2-yl]methyl benzoate

compound 33a

[(2S,4R,5R)-4-azido-5-methoxy-tetrahydrofuran-2-yl]methyl benzoate

TMSOTf

→

crude product

수율 29.3%

[(2S,4R,5R)-5-(5-amino-2,7-dioxo-6H-thiazolo[4,5-d]pyrimidin-3-yl)-4-azido-tetrahydrofuran-2-yl]methyl benzoate

수율 29.3%

용매

ACN

반응 조건

후처리

1. 1
   workup.ADDITIONwas added BSA (2.8 mg, 13.8 mmol)
2. 2
   기타The resulting reaction mixture
3. 3
   기타to form a clear solution
4. 4
   온도After the solution was cooled to room temperature
5. 5
   온도After being heated
6. 6
   workup.STIRRINGwith stirring at 70° C. for 14 hours
7. 7
   기타the solvent was removed in vacuo
8. 8
   기타The residue was partitioned between EtOAc and saturated NaHCO3 solution (30 mL)
9. 9
   기타The organic layer was separated
10. 10
    추출the aqueous phase was extracted with EtOAc (30 mL) twice
11. 11
    세척The combined organic layers were washed with brine
12. 12
    건조dried over Na2SO4
13. 13
    농축concentrated in vacuo

실험 절차

To a suspension of 5-amino-3,6-dihydrothiazolo[4,5-d]pyrimidine-2,7-dione (730 mg, 3.97 mmol) in ACN (15 mL) was added BSA (2.8 mg, 13.8 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, [(2S,4R,5R)-4-azido-5-methoxy-tetrahydrofuran-2-yl]methyl benzoate (compound 33a, crude, 1.1 g, 3.97 mmol) and TMSOTf (4.4 g, 19.5 mmol) were added in sequence. After being heated with stirring 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 500 mg crude product of [(2S,4R,5R)-5-(5-amino-2,7-dioxo-6H-thiazolo[4,5-d]pyrimidin-3-yl)-4-azido-tetrahydrofuran-2-yl]methyl benzoate (compound 33b) as a yellow solid. MS obsd. (ESI+) [(M+H)+]: 430.

출처