反应详情

6.35 g of ethyl 5-{(2RS,3SR)-3-hydroxy-2-(4-nitrophenyl)butyl}-2-furancarboxylate [the compound prepared in Reference Example 4(2)] was dissolved in 64 ml of vinyl acetate, and 2.66 ml of triethylamine was added. Then, 635 mg of immobilized lipase (Toyothium LIP) was added, and the reaction solution was stirred at room temperature for 5 days. The insolubles were filtered off, and the filtrate was evaporated under reduced pressure. The residue was purified by silica gel column chromatography [hexane/ethyl acetate=7/2→2/1] to give 2.93 g of ethyl 5-{(2S,3R)-3-acetoxy-2-(4-nitrophenyl)butyl}-2-furancarboxylate and 2.81 g of the title compound as colorless oily substances, respectively. The absolute steric configuration of the title compound was determined by the Mosher method (J.Am.Chem.Soc.), vol. 113, p. 4092 (1991)).

1. additionThen, 635 mg of immobilized lipase (Toyothium LIP) was added
2. filtrationThe insolubles were filtered off
3. customthe filtrate was evaporated under reduced pressure
4. customThe residue was purified by silica gel column chromatography [hexane/ethyl acetate=7/2→2/1]