Reagent Controlled Stereoselective Assembly of α-(1,3)-Glucans.

Reagent Controlled Stereoselective Assembly of α-(1,3)-Glucans.

European J Org Chem. 2019 Mar 14;2019(10):1994-2003

Authors: Wang L, Overkleeft HS, van der Marel GA, Codée JDC

Pre-activation based glycosylations have become a very powerful tool in the assembly of oligosaccharides and the use of nucleophilic additives allows for the in situ generation of reactive intermediates with tailored reactivity. We here use a glycosylation strategy that is based on the use of per-benzylated imidate building blocks for the fully stereoselective construction of a spacer equipped Aspergillus fumigatus α-1,3-octaglucan. We have used the trimethylsilyl iodide (TMSI)-triphenylphosphine oxide (Ph3P=O) for the stereoselective installation of an azidopropanol spacer and triflic acid (TfOH)-dimethyl formamide (DMF) enabled glycosylations for the coupling reactions with the secondary glucosyl C-3-alcohols. An operationally simple in situ activation coupling procedure is introduced and used for the final glycosylation events towards the octasaccharide.

PMID: 31007571 [PubMed]

Source: Industry