反应详情

To the solution of 4-amino-N-[(1,1-dimethylethoxy)carbonyl]-L-phenylalanine methyl ester (5.09 g, 17 mmol) in DMF (60 mL) was added Fmoc-D-Phenylalanine (8.70 g, 22.5 mmol), DIPEA (12 mL, 69 mmol) and HBTU (8.50 g, 22.5 mmol). The mixture was then stirred at room temperature for 4 h. The reaction mixture was diluted with water (150 mL) and the light yellow solid which precipitated was collected by filtration. This solid was then redissolved in 60 mL of acetone and the solution was treated with 100 mL of water. The solid was collected by filtration and was washed with 1N HCl, H2O. After drying at 60° C. under vaccum overnight, a light yellow solid was obtained (13.2 g). A portion of this solid (2.51 g, 3.78 mmol) was dissolved in 15 mL of DMF and to the solution was added 1.5 mL of piperidine. The above solution was stirred at room temperature for 45 min. After removal of the solvent, the residue was recrystillized from ethyl acetate-hexane to give N-[(1,1-dimethylethoxy)carbonyl]-4-[[(2R)-2-amino-1-oxo-3-phenylpropyl]amino]-L-phenylalanine methyl ester (1.36 g, 3.0 mmol) in 81.5% yield. LR MS 442 (M+H).

1. customthe light yellow solid which precipitated
2. filtrationwas collected by filtration
3. dissolutionThis solid was then redissolved in 60 mL of acetone
4. additionthe solution was treated with 100 mL of water
5. filtrationThe solid was collected by filtration
6. washwas washed with 1N HCl, H2O
7. customAfter drying at 60° C. under vaccum overnight
8. customa light yellow solid was obtained (13.2 g)
9. stirringThe above solution was stirred at room temperature for 45 min
10. customAfter removal of the solvent