反应详情

To a solution of 3-(S)-[(benzyloxycarbonyl)amino]-2-(R,S)-hydroxy-4-methylpentanoic acid (1.70 g, 6.04 mmol) and pyridine (4.9 mL) was added acetic anhydride (5.7 mL, 6.17 g, 60.4 mmol) dropwise at room temperature. The reaction was allowed to stir overnight and was diluted with ethyl acetate and washed with water (2×). The organic layer was dried over magnesium sulfate, filtered and evaporated in vacuo to give a thick oil. The residue was purified by column chromatography on silica gel with 15% methanol/dichloromethane to afford 1.56 g (80%) of 3-(S)-[(benzyloxycarbonyl)amino]-2-(R,S)-acetoxy-4-methyl pentanoic acid as a light yellow viscous oil. FAB MS [M+H] m/z; Calcd: 324, Found: 324.

1. washwashed with water (2×)
2. dry with materialThe organic layer was dried over magnesium sulfate
3. filtrationfiltered
4. customevaporated in vacuo
5. customto give a thick oil
6. customThe residue was purified by column chromatography on silica gel with 15% methanol/dichloromethane