反应详情

温度

20 °C

To a suspension of 1,3-dimethyl-1H-purine-2,6(3H,7H)-dione (20 g, 111 mmol) and K2CO3 (30.6 g, 222 mmol) in DMF (400 mL) was added (R)-methyl 2-((methylsulfonyl)oxy)propanoate (which may be synthesized according to the procedure described in PCT Pub No. WO/2005/059107 (40 g, 222 mmol). The reaction mixture was stirred at 20° C. for 20 h. The reaction mixture was then quenched with saturated NH4Cl(aq), diluted with water and extracted with CH2Cl2 (3×). The combined organic extracts were washed 3× with 10% LiCl (aq), dried over Na2SO4 and evaporated in vacuo. The residue was purified using silica gel column chromatography eluting first with PE:CH2Cl2 (1:1) followed by CH2Cl2:MeOH (50:1) to give 13.5 g (50.7 mmol, 45.7%, ee: 95%) of the (S)-product. The (S)-product was analyzed by chiral HPLC to determine it is at least 95% pure as the S-isomer (≧95% ee).

1. custommay be synthesized
2. customThe reaction mixture was then quenched with saturated NH4Cl(aq)
3. additiondiluted with water
4. extractionextracted with CH2Cl2 (3×)
5. washThe combined organic extracts were washed 3× with 10% LiCl (aq)
6. dry with materialdried over Na2SO4
7. customevaporated in vacuo
8. customThe residue was purified
9. washeluting first with PE
10. customto give 13.5 g (50.7 mmol, 45.7%, ee: 95%) of the (S)-product