American Chemical Society
ol301349w_si_001.pdf (5.55 MB)

Glycal Assembly by the in Situ Generation of Glycosyl Dithiocarbamates

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journal contribution
posted on 2012-07-06, 00:00 authored by Panuwat Padungros, Laura Alberch, Alexander Wei
Glycal assembly offers an expedient entry into β-linked oligosaccharides, but epoxyglycal donors can be capricious in their reactivities. Treatment with Et2NH and CS2 enables their in situ conversion into glycosyl dithiocarbamates, which can be activated by copper triflate for coupling with complex or sterically congested acceptors. The coupling efficiency can be further enhanced by in situ benzoylation, as illustrated in an 11-step synthesis of a branched hexasaccharide from glucals in 28% isolated yield and just four chromatographic purifications.