反应详情

0.22 g (0.64 mmol) of 2(RS)-[[(RS)-(ethoxy)[(2,5-dioxo-1 -imidazolidinyl)methyl]phosphinyl]methyl]-4-methylvaleric acid and 0.116 g (0.81 mmol) of L-leucine methylamide were taken up in 5 ml of dichloromethane and 2.5 ml of tetrahydrofuran. The solution was treated at -8° C. with 0.3 g (1.2 mmol) of N-ethoxycarbonyl-2-ethoxy-1,2-dihydroxyquinoline. The mixture was stirred at room temperature for 24 hours and was then left to stand at 0° C. for 48 hours. The solvent was removed by evaporation. The residue was taken up in 50 ml of chloroform. The solution was washed in sequence with 5% citric acid solution, 5% sodium hydrogen carbonate solution and sodium chloride solution, dried over anhydrous sodium sulfate and evaporated to give a gum. This gum was chromatographed on silica gel using chloroform/methanol(19:1) for the elution to give 0.08 g of [(2,5-dioxo-1-imidazolidinyl)methyl][(RS)-4-methyl-2-[[(S)-3-methyl-1-(methylcarbamoyl)butyl]carbamoyl]pentyl]phosphinic acid ethyl ester as a gum.

1. waitwas then left
2. waitto stand at 0° C. for 48 hours
3. customThe solvent was removed by evaporation
4. washThe solution was washed in sequence with 5% citric acid solution, 5% sodium hydrogen carbonate solution and sodium chloride solution
5. dry with materialdried over anhydrous sodium sulfate
6. customevaporated
7. customto give a gum
8. customThis gum was chromatographed on silica gel
9. washfor the elution