反应详情

A solution of [(1S,2S)-2-hydroxy-1-(3-oxo-propylcarbamoyl)-propyl]-carbamic acid benzyl ester (215 mg, 0.699 mmol, obtained from Reference Example 18) and a mixture of ethyl (2R,3R)-2-amino-3-hydroxy-3-[(2S,3R,4R,5R)-3,4-bis(acetyloxy)-5-(2,4-dioxo-3,4-dihydro-1(2H)-pyrimidinyl)tetrahydro-2-furanyl]propanoate and ethyl (2R,3R)-2-amino-3-hydroxy-3-[(2S,3R,4R,5S)-3,4-bis(acetyloxy)-5-(2,4-dioxo-3,4-dihydro-1(2H)-pyrimidinyl)tetrahydro-2-furanyl]propanoate (300 mg, 0.699 mmol) in anhydrous tetrahydrofuran (3 ml) were stirred at room temperature under a nitrogen atmosphere for 15 minutes. Acetic acid (40 μl) and sodium triacetoxyborohydride (0.296 mg, 1.4 mmole) were added and the resulting solution was stirred under nitrogen for an additional 2.5 hours. The reaction mixture was partitioned between ethyl acetate and aqueous sodium bicarbonate solution, and the aqueous layer was separated and extracted with ethyl acetate (2×75 ml). The combined extracts were washed with saturated sodium chloride solution, dried over sodium sulfate, filtered and concentrated in vacuo. The residue was chromatographed (flash column, silica gel, 5% methanol in methylene chloride) to provide ethyl (5S)-12-[(R)-[(2R,3R,4R,5S)-3,4-bis(acetyloxy)-5-(2,4-dioxo-3,4-dihydro-1(2H)-pyrimidinyl)tetrahydro-2-furanyl](hydroxy)methyl]-5-[(1S)-1-hydroxyethyl]-3,6-dioxo-1-phenyl-2-oxa-4,7,11-triazatridecan-13-oate (230 mg, 46%) as a white solid.

1. stirringthe resulting solution was stirred under nitrogen for an additional 2.5 hours
2. customThe reaction mixture was partitioned between ethyl acetate and aqueous sodium bicarbonate solution
3. customthe aqueous layer was separated
4. extractionextracted with ethyl acetate (2×75 ml)
5. washThe combined extracts were washed with saturated sodium chloride solution
6. dry with materialdried over sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customThe residue was chromatographed (flash column, silica gel, 5% methanol in methylene chloride)