Synthesis of C‐Glycopeptides via Free Radical Addition of Glycosyl Bromides to Dehydroalanine Derivatives

In only one reaction step, nonnatural C‐glycopeptides of type 1 can be obtained (see right, (S) form). This new class of molecules has remarkable properties; their high chemical stability recommends them as potential glycosidase inhibitors. The absolute configuration of the C‐glycopeptides can be elucidated with NMR spectroscopy and molecular dynamics calculations. (R¹,R² = H, OAc, sugar; R³,R⁴ = protecting group.) (Figure Presented.)