Solid-phase synthesis of glycopeptide carrying a tetra-N-acetyllactosamine-containing core 2 decasaccharide

Sialyl Tn Unit with TFA‐Labile Protection Realizes Efficient Synthesis of Sialyl Glycoprotein

“…Previously, the Bn protection strategy required a two‐step deprotection sequence at the end of the Fmoc‐SPPS: 1) a TFA treatment for the deprotection of the peptide portion; and 2) the low‐TfOH treatment to deprotect the carbohydrate chain. However, the low‐TfOH treatment sometimes cleaves some of the glycosidic linkages, especially when the glycan chain becomes large and complex . We have recently demonstrated that the use of substituted‐benzyl protecting groups, instead of the Bn group, achieves a one‐step deprotection at the end of the SPPS, eliminating the problem of the low‐TfOH treatment .…”

Analysis of carbohydrates and glycoconjugates by matrix‐assisted laser desorption/ionization mass spectrometry: An update for 2009–2010

“…Modification of glycosylation to effect deglycosylation of rhamnosylated drugs (Garnier et al, 2010) Gal-β-3GalNAc-α-Lys 5 TOF Immunogen design for tumor T antigen immuno-targeting (Sendra et al, 2009) Glycopolypeptide-based cholera toxin inhibitors MALDI Effect of peptide charge and glycan linker length on activity (Maheshwari et al, 2010) Glycopeptide carrying tetra-N-Ac-lactosamine containing core 2 decasaccharide TOF (DHB) Solid-phase synthesis (Ueki et al, 2010) Glycosaminoglycan-protein linkage tetraosyl peptide moieties of betaglycan TOF To investigate structures that best serve as a hexosamine acceptor for enzymatic glycosyl transfer (Tamura et al, 2010) Glycosulfopeptides from Nterminus of human endoglycan TOF/TOF (THAP)…”

Synthesis of Fmoc-Thr Unit Carrying Core 1O-Linked Sugar With Acid-SensitiveO-Protecting Group and Its Application to the Synthesis of Glycosylated Peptide Thioester

“…This method has been successfully used for the synthesis of various glycopeptides and glycoproteins. [5][6][7][8][9][10][11][12][13][14][15][16] The benzyl protection strategy for the carbohydrate moiety has several advantages over the more common acetyl protection strategy: (1) the benzyl-protected sugars usually retain higher reactivity during the glycosylation reactions, which is useful for the construction of complex sugar chains; (2) the benzyl groups are stable under the basic conditions used for the Fmoc-SPPS, which is free from side reactions, such as acyl migration from the carbohydrate to the terminal amino group of the growing peptide chain; and (3) the cleavage of the benzyl group does not require the alkaline conditions, such as NaOMe treatment, which have the potential danger of racemization of amino acid residues and β-elimination of the carbohydrate moiety. Instead, the complexity of this method is that a two-step deprotection is required at the end of the Fmoc-SPPS as follows: (1) TFA treatment to deprotect the peptide portion and (2) the Low-TfOH [17] treatment to deprotect the carbohydrate chain.…”

“…In addition, the Low-TfOH treatment sometimes decomposes a part of the glycosidic linkages when the structure of the Downloaded by [University of Newcastle, Australia] at 16:28 09 January 2015 carbohydrate chain becomes large and complex. [16] These are due to the fair stability of the benzyl group during the TFA treatment.…”