From mannosyl trichloroacetimidates

In the glycosylation step, a large excess of the donor, the benzoyl-protected mannosyl trichloroacetimidate, and a high concentration of TMSOTf in dichloromethane (DCM) or acetonitrile (ACN) were used, this protocol avoid the formation of the orthoester byproduct. Tbe different structures were synthesized with good yields, from 64% up to 86%, for the glycosylation and deprotection steps. 

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