Abstract
In cancer research, the development of vaccines against tumor-associated antigens
is of particular interest. Epithelial cells express mucin type glycoproteins, which
are extensively O-glycosylated. In case of cancer, the expression of these mucins is increased, and
their carbohydrate side chains show an aberrant glycosylation pattern. A set of single
and double glycosylated hexadecapeptides representing the tandem repeat sequence of
the epithelial mucin MUC4 carrying different tumor-associated carbohydrate antigens
was prepared by sequential solid-phase glycopeptide synthesis. The crucial glycosyl
amino acid building blocks containing the TN, T, sialyl-TN and (2,6)-sialyl-T antigens were synthesized according to a biomimetic strategy by
stepwise extension of the saccharide side chain of a Fmoc-protected galactosamine
threonine tert-butyl ester precursor.
Key words
glycopeptides - glycosylations - mucin MUC4 - sialyl-T antigen - solid-phase synthesis