Late-stage C(sp2)-H and C(sp3)-H glycosylation of C-aryl/alkyl glycopeptides: mechanistic insights and fluorescence labeling

Abstract

C(sp³)-H and C(sp²)-H glycosylations of structurally complex amino acids and peptides were accomplished through the assistance of triazole peptide-isosteres. The palladium-catalyzed peptide-saccharide conjugation provided modular access to structurally complex C-alkyl glycoamino acids, glycopeptides and C-aryl glycosides, while enabling the assembly of fluorescent-labeled glycoamino acids. The C-H activation approach represents an expedient and efficient strategy for peptide late-stage diversification in a programmable as well as chemo-, regio-, and diastereo-selective fashion.