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

ABSTRACT: 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.

SUBMITTER: Wang L

PROVIDER: S-EPMC6470887 | biostudies-other | 2019 Mar

REPOSITORIES: biostudies-other

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

Wang Liming L Overkleeft Herman S HS van der Marel Gijsbert A GA Codée Jeroen D C JDC

European journal of organic chemistry 20181004 10

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 <i>Aspergillus fumigatus</i> α-1,3-octaglucan. We have used the trimethylsilyl iodide (TMSI)-triphenylp ...[more]

PMID: 31007571

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