[NH2:1][C@H:2]1[CH2:7][O:6][C:5]([CH3:9])([CH3:8])[CH2:4][C@@H:3]1[OH:10].C(N(CC)CC)C.O1CCOCC1.O=C1CCC(=O)N1[C:31]([O:33][CH2:34][CH2:35][Si:36]([CH3:39])([CH3:38])[CH3:37])=[O:32]>C(OCC)(=O)C.O>[OH:10][C@H:3]1[CH2:4][C:5]([CH3:9])([CH3:8])[O:6][CH2:7][C@@H:2]1[NH:1][C:31](=[O:32])[O:33][CH2:34][CH2:35][Si:36]([CH3:39])([CH3:38])[CH3:37]To a solution of (4S,5S)-5-amino-2,2-dimethyl-tetrahydro-2H-pyran-4-ol (1.1 g, 4.0 mmol) and triethylamine (1.1 mL, 8.0 mmol) in a mixed solvent of dioxane (5 mL) and water (5 mL) at room temperature was added 2-(trimethylsilyl)ethyl 2,5-dioxopyrrolidine-1-carboxylate (1.2 g, 4.8 mmol). The reaction mixture was stirred at room temperature for 4 hours. After that, the solution was diluted with ethyl acetate and washed with brine. The organic layer was separated and concentrated. The resulting residue was purified by silica gel chromatography using petroleum ether/ethyl acetate=4/1 to 1/1 as the eluent to afford the title compound (1.0 g, 86% for 2 steps) as a yellow oil.
Wird geladen…
