Glycosyl alkoxythioimidates as building blocks for glycosylation: a reactivity study

Chemical O‐Glycosylations: An Overview

“…These donors showed similar properties to SBox glycosides and extensive studies were performed to compare the activation properties of the two. Activation of SNea donors with promoters like Cu(OTf) 2 , AgOTf, or MeOTf afforded the α ‐glycosides in significant yields . Other thioimidate S‐benzothiazolyl (SBaz) glycosides, 84 (Figure ), have also been commonly used for glycosylation.…”

SFox imidates as versatile glycosyl donors for chemical glycosylation

“…Analytical data for 15 was in accordance with that previously reported. 37 Methyl 4-O-(3,4,6-tri-O-benzoyl-2-O-benzyl-α-D-glucopyranosyl)-2,3,6-tri-O-benzyl-α-D-glucopyranoside (16). Was obtained from donor 4 and acceptor 9 by the general glycosylation procedure as a clear syrup in 28-60% yields (α only).…”

“…Our lab became interested in developing hybrid leaving groups, thioimidates. 4,5 As a result of this quest, S-benzoxazolyl (SBox), 6,7 S-thiazolinyl (STaz), 8,9 S-benzimidazolyl (SBiz) [10][11][12] and other thioimidates [13][14][15][16] were developed and used in various reactions and strategies. We have also investigated OBox imidates (Fig.…”

Transition‐Metal‐Mediated Glycosylation with Thioglycosides

“…N ‐Phenyltrifluorothioacetimidate leaving group activation was established in the presence of AgOTf among other reagents [97] . S ‐Glycosyl O ‐methyl phenylcarbamothioates (SNea) can be efficiently activated with Cu(OTf) 2 , [98] and the activation of various derivatives of SNea could also be affected with Cu(OTf) 2 , Bi(OTf) 3 , or AgOTf [99] …”

“…[97] S-Glycosyl O-methyl phenylcarbamothioates (SNea) can be efficiently activated with Cu-(OTf) 2 , [98] and the activation of various derivatives of SNea could also be affected with Cu(OTf) 2 , Bi(OTf) 3 , or AgOTf. [99] High affinity of gold catalysis to alkyne functionality is a relatively new research direction in glycosylation chemistry. First reported by Hotha et al for the activation of O-propargyl glycosides, [100] it was not until 2012 when Yu et al reported the use of gold catalysts with thioglycosides.…”