Divergent Synthesis of Core m1, Core m2 and Core m3 O‐Mannosyl Glycopeptides via a Chemoenzymatic Approach

Abstract

Comprehensive Summary O‐Mannosylation plays a vital role in the regulation of a variety range of biological processes, for instance, brain and muscle development. However, the precise function remains largely unknown due to its innate heterogeneity. In this regard, it is still welcome to develop efficient methods to access diverse structurally‐defined glycopeptides. In this study, a diversity‐oriented assembly of O‐mannosyl α‐dystroglycan (α‐DG) glycopeptides has been achieved via a chemoenzymatic strategy. This strategy features (i) gram scale divergent synthesis of core m1, core m2 and core m3 mannosylated amino acids from judiciously designed protecting group strategies and chemical glycosidation; (ii) efficient glycopeptide assembly via the optimized microwave‐assisted solid phase peptide synthesis (SPPS); and (iii) enzymatic elaboration of the core glycan structures to install galactosyl and sialyl‐galactosyl moieties. The efficiency and flexibility of this chemoenzymatic approach was demonstrated with the construction of 12 glycopeptides with different core m1, core m2 and core m3 mannosyl glycans, including a core m2 glycopeptide bearing a heptasaccharide for the first time.

Recent Advances in Glycopeptide and Glycoprotein Synthesis: A Refined Synthetic Probe towards the Biological World

“…reported a divergent synthesis of core m1, core m2 and core m3 O‐mannosyl glycopeptides via a chemoenzymatic approach. [ 64 ] Taking advantage of an orthogonally protected mannosyl module, three core structured O‐mannosyl amino acid building blocks can be accessible within minimal steps. Subsequent enzymatic galactosylation and sialylation, mediated by bacterial β1,4‐galactosyltransferase from Neisseria meningitidis (NmLgtB) and an α2,3‐sialyltransferase 1 M144D mutant from Pasteurella multocida (PmST1 M144D), further expanded the diversity of synthetic O‐mannosyl glycopeptides.…”

Synthesis of Core M3 Matriglycan Constituents via an Additive-Controlled 1,2-cis-Xylopyranosylation with O-Xylosyl Imidates as Donors

“…17,18 Recently, we developed a chemoenzymatic approach to assemble core M1, core M2, and core M3 O-mannosyl glycopeptides. 19 Hence, various efforts were devoted to the development of α-selective xylosidation methods in the past decades (Figure 2). Nifantiev and co-workers installed the acetyl group at 3-O of the xylopyranosyl donor to gain α-selectivity by remote assistance.…”

“…Recently, we developed a chemoenzymatic approach to assemble core M1, core M2, and core M3 O -mannosyl glycopeptides . However, extension of core M3 O -mannosyl glycans is more difficult, due to the lack of efficient synthesis methods.…”