478062-63-4Relevant academic research and scientific papers
Convenient high yield and stereoselective synthesis of O-glycopeptides using N-α-Fmoc-Tyr/Ser[β-D-Glc(OAc)4]OPfp generated in solution
Gangadhar, Beechanahalli P.,Jois, Seetharama D.S.,Balasubramaniam, Ambikaipakan
, p. 355 - 358 (2004)
Fmoc-AA-OPfp (AA=Tyr or Ser) (1 equiv) was reacted with β-D-Glc(OAc)5 (6 equiv) in the presence of BF 3.Et2O (6 equiv) in CH2Cl2 at room temperature for 2 h, and the glycosylation reaction mixture was used directly to couple to the amino group of the peptide resin without isolation and purification of the Fmoc-AA[β-D-Glc(OAc)4]-OPfp. Moreover, the -OAc protecting groups of glucose was removed just prior to releasing the peptide from the resin using 6 mM NaOMe in 85% DMF-MeOH. The crude product obtained by TFA cleavage contained >90% of the target O-glycopeptide, and the 500 MHz 1H NMR analysis revealed that the glycosylation reaction was nearly stereoselective (>97% β-anomer). This method is rapid and stereoselective, and can now be exploited for the routine synthesis of O-glycopeptides.
An orthogonally protected α,α-bis(aminomethyl)-β-alanine building block for the construction of glycoconjugates on a solid support
Katajisto, Johanna,Karskela, Tuomas,Heinonen, Petri,Loennberg, Harri
, p. 7995 - 8001 (2007/10/03)
Synthetic glycoclusters are extensively used as mimetics of naturally occurring, multivalent carbohydrate ligands in various glycobiological applications. Their preparation, however, is far from trivial, and it still is a limiting factor in the study of carbohydrate binding. We herein report the synthesis of an orthogonally protected building block, N-Alloc-N′-Boc-N″;-Fmoc-α,α-bis (aminomethyl)-β-alanine (1), and its use in the preparation of triantennary peptide glycoclusters (21-24) on a solid support. The assembly of the clusters involves removal of the amino protections of the solid-supported branching unit 1 in the order Fmoc, Boc, and Alloc, and subsequent coupling of peracetylated O-(glycopyranosyl)-N-Fmoc-L-serine pentafluorophenyl esters (galactose, glucose, mannose, and ribose) to each amino group exposed.
