2650-64-8

62234-40-6

The general procedure for the synthesis of (S)-4-amino-2-(((benzyloxy)carbonyl)amino)butyric acid from N-benzyloxycarbonyl-L-glutamine was as follows: 14 g of N-benzyloxycarbonyl-L-glutamine was dissolved in a solvent mixture of 80 mL of ethyl acetate and 20 mL of tetrahydrofuran, 50 mL of water was added, and the reaction mixture was cooled to 0°C. Subsequently, 60 g of bis(trifluoroacetic acid)iodobenzene were added slowly , and the reaction mixture was stirred at room temperature for 12 hours. After completion of the reaction, the aqueous layer was separated and the organic layer was washed three times with distilled water. All aqueous layers were combined and concentrated by vacuum distillation. The concentrated aqueous solution was stirred with anhydrous ethanol to promote crystallization and the crystalline product was collected by filtration. The crystals were washed twice with ethanol and dried by filtration. Finally, the product was dried at 60°C to give 5 g of the target compound with a melting point of 182-186°C.