Synthesis of Glucuronoxylan Hexasaccharides by Preactivation‐Based Glycosylations

Underlin, Emilie Nørmølle; d’Errico, Clotilde; Böhm, Maximilian Felix; Madsen, Robert

doi:10.1002/ejoc.202000211

Cited by 4 publications

(2 citation statements)

References 46 publications

(39 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover, the acidic pentasaccharide related to the O-antigenic polysaccharide of Escherichia coli 120 with its pmethoxyphenyl (PMP) glycoside 70 and the cell surface phospholipomannan anchor 71 of Candida albicans have been synthesized. Plant carbohydrates such as arabinoxylans 72 and glucuronoxylans 73 are also readily accessible via the preactivation-based one-pot protocol.…”

Section: Various Oligosaccharide Syntheses In Other Research Groupsmentioning

confidence: 99%

Donor Preactivation-Based Glycan Assembly: from Manual to Automated Synthesis

Yao,

2024

Acc. Chem. Res.

View full text Add to dashboard Cite

Conspectus Carbohydrates are called the third chain of life. Carbohydrates participate in many important biochemical functions in living species, and the biological information carried by them is several orders of magnitude larger than that of nucleic acids and proteins. However, due to the intrinsic complexity and heterogeneity of carbohydrate structures, furnishing pure and structurally well-defined glycans for functional studies is a formidable task, especially for homogeneous large-size glycans. To address this issue, we have developed a donor preactivation-based one-pot glycosylation strategy enabling multiple sequential glycosylations in a single reaction vessel. The donor preactivation-based one-pot glycosylation refers to the strategy in which the glycosyl donor is activated in the absence of a glycosyl acceptor to generate a reactive intermediate. Subsequently, the glycosyl acceptor with the same anomeric leaving group is added, leading to a glycosyl coupling reaction, which is then iterated to rapidly achieve the desired glycan in the same reactor. The advantages of this strategy include the following: (1) unique chemoselectivity is obtained after preactivation; (2) it is independent of the reactivity of glycosyl donors; (3) multiple-step glycosylations are enabled without the need for intermediate purification; (4) only stoichiometric building blocks are required without complex protecting group manipulations. Using this protocol, a range of glycans including tumor-associated carbohydrate antigens, various glycosaminoglycans, complex N-glycans, and diverse bacterial glycans have been synthesized manually. Gratifyingly, the synthesis of mycobacterial arabinogalactan containing 92 monosaccharide units has been achieved, which created a precedent in the field of polysaccharide synthesis. Recently, the synthesis of a highly branched arabinogalactan from traditional Chinese medicine featuring 140 monosaccharide units has been also accomplished to evaluate its anti-pancreatic-cancer activity. In the spirit of green and sustainable chemistry, this strategy can also be applied to light-driven glycosylation reactions, where either UV or visible light can be used for the activation of glycosyl donors. Automated synthesis is an advanced approach to the construction of complex glycans. Based on the two preactivation modes (general promoter activation mode and light-induced activation mode), a universal and highly efficient automated solution-phase synthesizer was further developed to drive glycan assembly from manual to automated synthesis. Using this synthesizer, a library of oligosaccharides covering various glycoforms and glycosidic linkages was assembled rapidly, either in a general promoter-activation mode or in a light-induced-activation mode. The automated synthesis of a fully protected fondaparinux pentasaccharide was realized on a gram scale. Furthermore, the automated synthesis of large-size polysaccharides was performed, allowing the assembly of arabinans up to an astonishing 1080-mer using the automate...

show abstract

Section: Various Oligosaccharide Syntheses In Other Research Groupsmentioning

confidence: 99%

Donor Preactivation-Based Glycan Assembly: from Manual to Automated Synthesis

Yao,

2024

Acc. Chem. Res.

View full text Add to dashboard Cite

show abstract

“…In so doing, we anticipated that this target could be attained by preparing (and then coupling) the suitably activated forms, 2 – 5 (Figure 2 ), of the component disaccharide, keystone, branching and capping fragments, respectively, of target 1 . 12…”

mentioning

confidence: 99%