Ethyl chloroformate → 4-{[4-({[4-(4,5-dihydro-1,3-oxazol-2-ylmethyl)-1-phenyl-1H-pyrazol-3-yl]oxy}methyl)-2-methoxyphenoxy]methyl}-2-(2-furyl)-5-methyl-1,3-oxazole

関与物質

反応手順

To a mixture of {3-[(4-{[2-(2-furyl)-5-methyl-1,3-oxazol-4-yl]methoxy}-3-methoxybenzyl)oxy]-1-phenyl-1H-pyrazol-4-yl}acetic acid (0.70 g), triethylamine (0.17 g) and tetrahydrofuran (30 mL) was added ethyl chlorocarbonate (0.18 g) at −30° C., and the mixture was stirred at the same temperature for 40 min. The reaction mixture was added to a mixture of 1-amino-2-chloroethane hydrochloride (0.81 g), triethylamine (0.71 g) and tetrahydrofuran (20 mL) at −30° C., and the mixture was stirred at room temperature for 1 hr. Water was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The organic layer was washed with saturated brine, dried over anhydrous magnesium sulfate and concentrated. A mixture of the obtained residue, potassium carbonate (0.24 g) and N,N-dimethylformamide (20 mL) was stirred at 90° C. for 2 hrs. Water was poured into the reaction mixture, and the mixture was extracted with ethyl acetate. The organic layer was washed with saturated brine, dried over anhydrous magnesium sulfate and concentrated. The residue was subjected to silica gel column chromatography to give 4-{[4-({[4-(4,5-dihydro-1,3-oxazol-2-ylmethyl)-1-phenyl-1H-pyrazol-3-yl]oxy}methyl)-2-methoxyphenoxy]methyl}-2-(2-furyl)-5-methyl-1,3-oxazole as colorless crystals (0.14 g, yield 18%) from a fraction eluted with ethyl acetate-methanol (50:1, v/v). Recrystallization from ethyl acetate-hexane gave colorless prism crystals. melting point: 95-96° C.

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