Removal of Acyl Protective Groups from Glycopeptides - American

Does Not Epimerize Peptide Stereocenters, and β-Elimination Is. Slow. Petter Sjölin, Mikael Elofsson, and Jan Kihlberg*. Department of Organic Chemi...
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J. Org. Chem. 1996, 61, 560-565

Removal of Acyl Protective Groups from Glycopeptides: Base Does Not Epimerize Peptide Stereocenters, and β-Elimination Is Slow Petter Sjo¨lin, Mikael Elofsson, and Jan Kihlberg* Department of Organic Chemistry 2, Center for Chemistry and Chemical Engineering, The Lund Institute of Technology, Lund University, P.O. Box 124, S-221 00 Lund, Sweden Received October 6, 1995X

Epimerization of glycopeptide stereocenters and β-elimination have been considered as important potential side reactions on deacylation of glycopeptides which have the carbohydrate moieties protected with O-acyl groups. Since no systematic investigation of these side reactions has been reported, a model acetylated, O-linked glycotripeptide and its three epimers at the R-carbon stereocenters were prepared. The model glycopeptide did not undergo any epimerization (