反应详情

To a solution of 10.00 g (S)-2-tert-butoxycarbonylamino-pentanedioic acid 1-benzyl ester in 80 ml DMF were added 5.85 g EDC, 4.67 g HOBt, 10.8 ml DIPEA and 3.2 ml benzylamine at 0° C. After stirring for 12 h the reaction mixture was concentrated, the residue was dissolved in dichloromethane and subsequently extracted with aqueous LiCl (4%), 0.1 M HCl and saturated aqueous NaHCO3. The crude product obtained after evaporation of the solvent was purified by flash chromatography on silica using ethyl acetate/heptane 1:1 as eluent. Yield: 11.2 g colorless amorphous solid.

1. concentrationwas concentrated
2. dissolutionthe residue was dissolved in dichloromethane
3. extractionsubsequently extracted with aqueous LiCl (4%), 0.1 M HCl and saturated aqueous NaHCO3