Tetrahydrofuran → N-{(S)-2-hydroxy-1-[(2S,4S)-4-isopropyl-5-oxotetrahydrofuran-2-yl]ethyl}-2-nitrobenzenesulfonamide

Participants

Reaction Steps

14 ml of triethylamine (101 mmol) and 11.12 g of O-nitrobenzenesulfonyl chloride (50.1 mmol) were added to a solution of 8.50 g of (3S,5S)-5-[(S)-1-amino-2-hydroxyethyl]-3-isopropyldihydrofuran-2-one hydrochloride obtained in the above reaction (33.5 mmol) in a mixed solvent of tetrahydrofuran (170 ml) and water (17 ml) at room temperature, and the mixture was stirred at the same temperature for 12 hours. The reaction mixture was concentrated under reduced pressure, followed by extraction with ethyl acetate. Then, the organic layer was washed with water, a saturated sodium bicarbonate aqueous solution and brine and dried over anhydrous magnesium sulfate. After filtration, the solvent was evaporated under reduced pressure, and the residue was purified by silica gel column chromatography (elution solvent:ethyl acetate). Further, 110 ml of diisopropyl ether and 11 ml of ethyl acetate were added, and the precipitated solid was collected by filtration to obtain 8.78 g of the title compound (total yield over two steps: 70%).

Provenance & Evidence