Thioglycosides in Carbohydrate Research

Glycosylation Reaction of <i>Thioglycosides</i> by Using Hypervalent Iodine(III) Reagent as an Excellent Promoter

“…Since the first report in 1909, the chemistry of thioglycosides has been significantly investigated and numerous methodologies have been reported on their preparation and activation in the past three decades. [1][2][3][4][5] Thioglycoside donors are relatively easy to prepare, stable under various reaction conditions of protection and deprotection, and offer orthogonality in their activation. 6) An important feature of thioglycosides is their ability to serve not only as glycosyl donors, but also acceptors.…”

“…This feature, as the tunable reactivity of thioglycosides, has often been used for the synthesis of various oligosaccharides. 7) In general, the activation of thioglycosides was performed using a mercury salt, such as HgSO 4 , HgCl 2 , Hg(OBz) 2 , or Hg(NO 3 ) 2 . [8][9][10][11] The use of copper(II) trifluoromethanesulfonate Cu(OTf) 2 (Mukaiyama) or CuBr 2 -Bu 4 NBr-AgOTf (Ogawa and Ito) as an activator was further investigated.…”

“…7) In general, the activation of thioglycosides was performed using a mercury salt, such as HgSO 4 , HgCl 2 , Hg(OBz) 2 , or Hg(NO 3 ) 2 . [8][9][10][11] The use of copper(II) trifluoromethanesulfonate Cu(OTf) 2 (Mukaiyama) or CuBr 2 -Bu 4 NBr-AgOTf (Ogawa and Ito) as an activator was further investigated. 12,13) Recently, In(OTf) 3 was reported to become an effective activator by ball milling under a solvent-free condition.…”

A Photoswitchable Trivalent Cluster Mannoside to Probe the Effects of Ligand Orientation in Bacterial Adhesion

“…Because thioglycosides are known to be bench‐stable and efficient donors in glycosylation reactions, compound 7 was also considered as mannosyl donor. However, standard activation with an excess of N ‐iodosuccinimide (NIS) and a catalytic amount of triflic acid (TfOH) in dichloromethane was ineffective and only a trace of the desired glycocluster product was observed by TLC analysis, with most of the donor remaining unreacted.…”

A novel O -fucosylation strategy preactivated by ( p -Tol) 2 SO/Tf 2 O and its application for the synthesis of Lewis blood group antigen Lewis a

“…Among these donors, thioglycoside was the most frequently used one, since thioglycoside was convenient to prepare and stable under many reaction conditions. 16 Preactivation is an important strategy for glycosylation, and many complex oligosaccharides were successfully synthesized. 17 In recent years, the (p-Tol) 2 SO/Tf 2 O preactivation system, which was derived from the traditional Ph 2 SO/Tf 2 O pair, 17d has been confirmed to be a practical, straightforward, and high stereoselectivity protocol for O-and Cglycosylations when employing N-acetyl-5-N,4-O-oxazolidione protected thiosialoside as donor.…”