Water → (5R)-2-(5-{3-[(1S)-2-Methoxy-1-methylethoxy]-5-[(triisopropylsilyl)oxy)phenyl]-1H-pyrrol-2-yl)-5{[(triisopropylsilyl)oxy]methyl}-4,5-dihydro-1,3-oxazole

Participants

Reaction Steps

N-{(2S)-2-Hydroxy-3-[(triisopropylsilyl)oxy]propyl}-5-{3-[(1S)-2-methoxy-1-methylethoxy]-5-[(triisopropylsilyl)oxy]phenyl}-1H-pyrrole-2-carboxamide (10.54 g, 15.6 mmol) synthesized in Example (125e) was dissolved in tetrahydrofuran (160 mL), and anhydrous methanesulfonic acid (5.51 g, 31.6 mmol) and triethylamine (8.70 mL, 62.4 mmol) were added, followed by stirring at room temperature for 3 hours under nitrogen atmosphere, and subsequently the temperature was raised to 60° C., followed by stirring for 3 hours. To the reaction solution, water (200 mL) was added, and extraction was carried out with ethyl acetate (300 mL). The organic layer was washed with saturated brine, and subsequently dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure, and the resulting residue was purified using silica gel column chromatography (elution solvent: ethyl acetate/hexane=5%-30%) to afford the desired compound (9.72 g, yield 95%) as a brown oil.

Provenance & Evidence