Total synthesis of erythropoietin through the development and exploitation of enabling synthetic technologies.

A convergent and operationally simple method for the preparation of N-linked glycopeptides was highlighted in the preparation of three glycopeptide fragments of erythropoietin. These fragments were assembled by ligation chemistry in the first total synthesis of erythropoietin bearing four glycans. This methodology should find far-reaching applications in the synthesis of a whole range of glycoproteins for biological study.