反应详情

Boc-L-Ile-OH ½ H2O (3.92 g, 16.8 mmol), H-D,L-Pip-OBzl HCl (3.57 g, 12 mmol) and HATU (7.75 g, 18 mmol) were dissolved in DMF (15 ml), mixed with Et3N (4.76 ml, 30 mmol) under ice cooling, and then stirred overnight. The reaction mixture was concentrated, extracted with ethyl acetate (120 ml), and washed twice with 10% citric acid, 4% NaHCO3 and then brine, respectively. After drying over magnesium sulfate, ethyl acetate was distilled off. The residue was vacuum dried and purified by flash chromatography (3.5×20 cm) with CHCl3/MeOH (99:1) to yield Boc-L-Ile-D,L-Pip-OBzl (5.90 g, 13.8 mmol; yield 97%) as an oil.

1. concentrationThe reaction mixture was concentrated
2. extractionextracted with ethyl acetate (120 ml)
3. washwashed twice with 10% citric acid, 4% NaHCO3
4. dry with materialAfter drying over magnesium sulfate, ethyl acetate
5. distillationwas distilled off
6. customdried
7. custompurified by flash chromatography (3.5×20 cm) with CHCl3/MeOH (99:1)