Encouraging Progress in the omega-Aspartylation of Complex Oligosaccharides as a General Route to beta-N-Linked Glycopolypeptides

Laboratory for Bioorganic Chemistry, Sloan-Kettering Institute for Cancer Research, 1275 York Avenue, New York, New York 10065, United States.
Journal of the American Chemical Society (Impact Factor: 11.44). 02/2011; 133(5):1597-602. DOI: 10.1021/ja110115a
Source: PubMed

ABSTRACT Described herein is a method for the joining of complex peptides to complex oligosaccharides via an N-linkage. The ω-aspartylation is conducted by coupling fully deprotected glycosylamine with a peptide containing a unique thioacid at the ω-aspartate carboxyl. In the presence of HOBT, under conditions that, in principle, allow for oxidation, complex components are combined in encouraging yields to produce structurally and stereochemically defined N-linked glycopolypeptides wherein the carbohydrate domain can be quite complex. Various mechanisms for oxidative coupling are proposed.

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