N-Acetyl-muramyl-L-alanyl-D-glutamic

The synthesis of the a-methyl ester of N-acetyl-muramyl-L-alanyl-D-glutamic acid (21) 45) and the ot-methyl ester of N-acetylmuramyl-L-alanyl-D-glutamine (22) 47), starts with the preparation of BOC-L-Ala-D-Glu(OBzl) and Z-L-Ala-D-Gln respectively which were esterified by means of diazomethane. 

Lefrancier, P., M. Petitou, M. Level, M. Derrien, J. Choay, and E. Lederer Synthesis of N-acetyl-muramyl-L-alanyl-D-glutamic ot-amide (MDP) or a-methyl ester derivatives, bearing a lipophilic group at the C-terminal peptide end. Int. J. Peptide Protein Res. 14, 437 (1979). 

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