反应详情

To 80 mg of 5-chloro-4-isopropoxy-3-methyl-benzofuran-2-carboxylic acid was added 121 mg of (S)-2-(4′-amino-biphenyl-4-sulfonylamino)-3-methyl-butyric acid tert-butyl ester, 159 mg of BOP, 46 mg of N,N-diisopropylethylamine and 4 mL of DMF. The mixture was stirred at room temperature for 48 h. The mixture was addedbrine and was extracted with ethyl acetate. The combined ethyl acetate solution was washed with brine. Removal of the solvent and purification of the residue by column chromatography on silica gel gave 178 mg (98% yield) of (S)-2-{4′-[(5-chloro-4-isopropoxy-3-methyl-benzofuran-2-carbonyl)-amino]-biphenyl-4-sulfonylamino}-3-methyl-butyric acid tert-butyl ester as a colorless semi-solid.

1. extractionwas extracted with ethyl acetate
2. washThe combined ethyl acetate solution was washed with brine
3. customRemoval of the solvent and purification of the residue by column chromatography on silica gel