Solid-phase synthesis and characterization of O-dimannosylated heptadecapeptide analogues of human insulin-like growth factor 1 (IGF-1)

Abstract

N ^α -Fmoc-3-O-[Ac₄-α-D-Manp-(1→2)-Ac₃-α-D-Manp-1-]-Thr-OPfp, 7, and N^α-Fmoc-3-O-[Ac₄-α-D-Manp-(1→2)-Ac₃-α-D-Manp-1-]-Ser-OPfp, 8, were prepared and used as building blocks in automated continuous-flow solid-phase glycopeptide synthesis of two O-glycosylated heptadecapeptide analogues of human insulin-like growth factor 1. The corresponding non-glycosylated fragments were also prepared, and comparative NMR studies regarding the influence of the sugar moiety on the peptide backbone showed only limited effects due to glycosylation.