Construction of highly glycosylated mucin-type glycopeptides based on microwave-assisted solid-phase syntheses and enzymatic modifications.

摘要: A MUC1-related glycopeptide having five core-2 hexasaccharide branches (C330H527N46O207, MW = 8450.9) was synthesized by a new strategy using combination of microwave-assisted solid-phase synthesis (MA-SPGS) and enzymatic sugar elongation. Synthesis key intermediate best achieved in PEGA [poly(ethylene glycol)-poly-(N,N-dimethylacrylamide) copolymer] resin MA-SPGS glycosylated amino acid building blocks with high speed purity. Deprotection the subsequent glycosyltransferase-catalyzed elongations were performed for generation additional diversities moieties glycopeptides β1,4-galactosyltransferase (β1,4-GalT) two kinds α2,3-sialyltransferases [ST3Gal III; α2,3-(N)-SiaT ST3Gal II; α2,3-(O)-SiaT]. These reactions proceeded successfully presence 0.2% Triton X-100 to convert chemically trisaccharide glycans disialylated hexasaccharide.