反应详情

温度

0 °C

A solution of 2-{(2S,3S)-2-[(R)-2-amino-2-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-acetylamino]-3-phenyl-butyrylamino}-thiazole-4-carboxylic acid methyl ester (0.380 g, 0.75 mmol)) and diisopropylethylamine (0.52 mL, 3 mmol) in tetrahydrofuran (7.5 mL) were added to a solution of diphosgene (0.48 mL, 4 mmol) in a mixture of toluene (7.5 mol) and tetrahydrofuran (7.5 mol) over 10 minutes at 0° C. The mixture was stirred at 0° C. for 20 minutes and then diluted with ethyl acetate. The mixture was washed with water, brine and dried (sodium sulfate). Evaporation of the solvents and chromatography of the residue over silica gel gradient eluted with 0.2-1% methanol in dichloromethane gave (2-{(2S,3S)-2-[(R)-4-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2,5-dioxo-imidazolidin-1-yl]-3-phenyl-butyrylamino}-thiazole-4-carboxylic acid methyl ester (0.22 g, 55%).

1. washThe mixture was washed with water, brine
2. dry with materialdried (sodium sulfate)
3. customEvaporation of the solvents and chromatography of the residue over silica gel gradient
4. washeluted with 0.2-1% methanol in dichloromethane