反应详情

0.208 g of dicyclohexylcarbodiimide, 0.124 g of hydroxybenzotriazole and 0.106 g of N-ethylmorpholine were added to a stirred solution of 0.315 g of N2 -[3(S)-amino-2(R)-hydroxy-4-phenylbutyl]-N1 -phenyl-L-prolinamide add 0.244 g of N-(benzyloxycarbonyl)-L-asparagine in 10 ml of tetrahydrofuran at 0° C. The mixture was stirred for 16 hours, then diluted with ethyl acetate and filtered. The filtrate was washed with sodium bicarbonate solution and sodium chloride solution and the solvent was then removed by evaporation. The residue was chromatographed on silica gel using dichloromethane/methanol (9:1) for the elution to give 0.22 g of N2 -[3(S)-[[N-(benzyloxycarbonyl)-L-asparaginyl]amino]-2(R)-hydroxy-4-phenylbutyl]-N1 -phenyl-L-prolinamide in the form of a white solid of melting point 169°-171° C. (from methanol).

1. filtrationfiltered
2. washThe filtrate was washed with sodium bicarbonate solution and sodium chloride solution
3. customthe solvent was then removed by evaporation
4. customThe residue was chromatographed on silica gel
5. washfor the elution