Triethylamine → N-[(1,1-Dimethylethoxy)carbonyl]-D-alanine 2,5-dioxo-1-pyrrolidinyl ester

Participants

Reaction Steps

To a solution of Boc-(D)-mesoDAP-(L)-D-AlaOH-(D)-NHNHBoc (2) (2.76 g) and triethylamine in aceton-water (2:1, 90 ml) was added a solution of O-acetylbenziloyl-γ-D-Glu(α-OBzl)-1-succinimidyl ester (3.4 g: 5.8 mM) in acetone at 0° C. with stirring. Stirring was continued overnight, allowing the temperature of the mixture to reach to room temperature. After evapolation of acetone, the residue was added ethyl acetate (60 ml), and the organic layer was washed with dil sodium bicarbonate, saturated sodium chloride, dil hydrochloric acid and water. After drying over magnesium sulfate, the solvent was removed in vacuo and triturated with isopropyl ether to give O-acetylbenziloyl-γ-D-Glu(α-OBzl)-(L)-Boc-(D)-mesoDAP-(L)-D-AlaOH-(D)-NHNHBoc (3) (4.63 g).

Provenance & Evidence