反应详情

To a solution of tert-butyl (5S,12S)-12-[(R)-[(3R,4R,5R)-3,4-bis{[tert-butyl(dimethyl)silyl]oxy}-5-(3-(4-methoxybenzyl)-2,4-dioxo-3,4-dihydro-1(2H)-pyrimidinyl)tetrahydro-2-furanyl](hydroxy)methyl]-5-isobutyl-3,6-dioxo-1-phenyl-2-oxa-4,7,11-triazatridecan-13-oate (420 mg, 0.409 mmol, obtained from Example 4) in acetonitrile (20 ml) was added a solution of ammonium cerium(IV) nitrate (898 mg, 1.6 mmol) in water (4 ml). The resulting solution was stirred for 48 hours at room temperature, and saturated sodium chloride aqueous solution was added. The aqueous layer was extracted with ethyl acetate (3×75 mL). The combined extracts were washed with saturated sodium chloride, dried over sodium sulfate, filtered and concentrated in vacuo. The resultant residue was chromatographed (flash column, silica gel, 5% methanol in methylene chloride) to provide tert-butyl (5S,12S)-12-[(R)-[(3R,4R,5R)-3,4-bis{[tert-butyl(dimethyl)silyl]oxy}-5-(2,4-dioxo -3,4-dihydro-1(2H)-pyrimidinyl)tetrahydro-2-furanyl](hydroxy)methyl]-5-isobutyl-3,6-dioxo-1-phenyl-2-oxa-4,7,11-triazatridecan-13-oate (91 mg, 25%) as a pale tan amorphous solid.

1. extractionThe aqueous layer was extracted with ethyl acetate (3×75 mL)
2. washThe combined extracts were washed with saturated sodium chloride
3. dry with materialdried over sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated in vacuo
6. customThe resultant residue was chromatographed (flash column, silica gel, 5% methanol in methylene chloride)