Stereospecific 1,2-cis-glycosylation: a modified thiocyanate method

Kochetkov, N. K.; Klimov, E. M.; Malysheva, N. N.; Demchenko, Alexei V.

doi:10.1016/s0008-6215(00)91007-3

Cited by 19 publications

(10 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In our hands, however, their activation over the STaz leaving group was somewhat inconsistent. 15 With the reinvestigation of glycosyl thiocyanates, reactive glycosyl donors introduced by Kochetkov, 26–28 we determined that their activation can be reliably achieved with Cu(OTf) 2 , reaction conditions under which STaz group reacts sluggishly. 29 Indeed, Cu(OTf) 2 -promoted activation of thiocyanate donor 50 over STaz glycosyl acceptor 12 was very efficient and the resulting disaccharide 14 was isolated in 89% yield (Scheme 3).…”

Section: Resultsmentioning

confidence: 99%

On Orthogonal and Selective Activation of Glycosyl Thioimidates and Thioglycosides: Application to Oligosaccharide Assembly

Kaeothip

Demchenko

2011

J. Org. Chem.

View full text Add to dashboard Cite

Discrimination amongst S-thiazolinyl (STaz), S-benzoxazolyl (SBox), and S-ethyl anomeric leaving group was achieved by fine-tuning of the activation conditions. Preferential glycosidation of a certain leaving group is neither determined by the strength of activating reagents nor the stability of the leaving group itself; instead, the type of activation comes to the fore and plays the key role. The activation conditions established herein were applied to a sequential five-step synthesis of a hexasaccharide using six monosaccharide building blocks equipped with six different leaving groups.

show abstract

Section: Resultsmentioning

confidence: 99%

On Orthogonal and Selective Activation of Glycosyl Thioimidates and Thioglycosides: Application to Oligosaccharide Assembly

Kaeothip

Demchenko

2011

J. Org. Chem.

View full text Add to dashboard Cite

show abstract

“…This step can be either reversible or irreversible depending on the type of the leaving group used and the method of activation . There are a few reports indicating that the glycosyl acceptor attack may be directed to the activated donor. − This S N 2-like displacement pathway is quite desirable because it would allow for the stereospecific inversion of the leaving group. Step 2.…”

Section: Traditional Manual Synthesis Of Oligosaccharidesmentioning

confidence: 99%

Automated Chemical Oligosaccharide Synthesis: Novel Approach to Traditional Challenges

et al. 2018

View full text Add to dashboard Cite

Advances in carbohydrate chemistry have certainly made common oligosaccharides much more accessible. However, many current methods still rely heavily upon specialized knowledge of carbohydrate chemistry. The application of automated technologies to chemical and life science applications such as genomics and proteomics represents a vibrant field. These automated technologies also present opportunities for their application to organic synthesis, including that of the synthesis of oligosaccharides. However, application of automated methods to the synthesis of carbohydrates is an underdeveloped area as compared to other classes of biomolecules. The overarching goal of this review article is to present the advances that have been made at the interface of carbohydrate chemistry and automated technology.

show abstract

“…The method was also applied for mannosylation reactions but with no selectivity . The thiocyanate method was later modified to use TMSOTf (0.2 equiv) as the catalyst and alcohols as acceptors in the presence of 4 Å molecular sieves . The high degree of stereospecificity of the 1,2- cis selective glycosylation was demonstrated by a trityl-thiocyanate polycondensation to give α-1,6- d -glucan fragments .…”

Section: Thiocyanatesmentioning

confidence: 99%

“…755 The thiocyanate method was later modified to use TMSOTf (0.2 equiv) as the catalyst and alcohols as acceptors in the presence of 4 Å molecular sieves. 756 The high degree of stereospecificity of the 1,2-cis selective glycosylation was demonstrated by a trityl-thiocyanate polycondensation to give α-1,6-D-glucan fragments. 757 Despite the promising results using thiocynates, the method has not become widely applicable.…”

Section: Thiocyanatesmentioning

confidence: 99%

Catalytic Glycosylations in Oligosaccharide Synthesis

2018

View full text Add to dashboard Cite

Catalytic glycosylation has been a central reaction in carbohydrate chemistry since its introduction by Fischer 125 years ago, but it is only in the past three to four decades that catalytic methods for synthesizing oligosaccharides have appeared. Despite the development of numerous elegant and ingenious catalytic glycosylation methods, only a few are in general use. This review covers all methods of catalytic glycosylation with the focus on the development and application in oligosaccharide synthesis and provide an overview of the scope and limitations of these. The review also includes relevant mechanistic studies of catalytic glycosylations. The future of catalytic glycosylation chemistry is discussed, including specific, upcoming methods and possible directions for the field of research in general.

show abstract

Stereospecific 1,2-cis-glycosylation: a modified thiocyanate method

Cited by 19 publications

References 8 publications

On Orthogonal and Selective Activation of Glycosyl Thioimidates and Thioglycosides: Application to Oligosaccharide Assembly

On Orthogonal and Selective Activation of Glycosyl Thioimidates and Thioglycosides: Application to Oligosaccharide Assembly

Automated Chemical Oligosaccharide Synthesis: Novel Approach to Traditional Challenges

Catalytic Glycosylations in Oligosaccharide Synthesis

Contact Info

Product

Resources

About