Advances in glycoside and oligosaccharide synthesis

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 52(22), P. 7773 - 7801

Published: Jan. 1, 2023

The structural complexity of glycans poses a serious challenge in the chemical synthesis glycosides, oligosaccharides and glycoconjugates. Glycan complexity, determined by composition, connectivity, configuration far exceeds what nature achieves with nucleic acids proteins. Consequently, glycoside ranks among most complex tasks organic synthesis, despite involving only simple type bond-forming reaction. Here, we introduce fundamental principles bond formation summarize recent advances oligosaccharide synthesis.

Language: Английский

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One-Pot Assembly of Mannose-Capped Lipoarabinomannan Motifs up to 101-Mer from the Mycobacterium tuberculosis Cell Wall

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(6), P. 4112 - 4122

Published: Jan. 16, 2024

Lipoarabinomannan (LAM) from the Mycobacterium tuberculosis cell envelope represents important targets for development of new therapeutic agents against tuberculosis, which is a deadly disease that has plagued mankind long time. However, accessibility long, branched, and complex lipoarabinomannan over 100-mer remains long-standing challenge. Herein, we report modular synthesis mannose-capped 101-mer M. wall using one-pot assembly strategy on basis glycosyl ortho-(1-phenylvinyl)benzoates (PVB), not only accelerates but also precludes potential problems associated with glycosylation thioglycosides. Shorter sequences including 18-mer, 19-mer, 27-mer are synthesized in-depth structure–activity relationship biological studies. Current synthetic routes highlight following features: (1) streamlined various linear branched glycans orthogonal combination N-phenyltrifluoroacetimidates, ortho-alkynylbenzoates, PVB; (2) highly stereoselective construction 10 1,2-cis-arabinofuranosyl linkages 5-O-(2-quinolinecarbonyl)-directing 1,2-cis-arabinofuranosylation via hydrogen-bond-mediated aglycone delivery strategy; (3) convergent [(18 + 19) × 2 27] LAM polysaccharide. The present work demonstrates this can streamline chemical polysaccharides.

Language: Английский

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Efficient O- and S-glycosylation with ortho-2,2-dimethoxycarbonylcyclopropylbenzyl thioglycoside donors by catalytic strain-release

Chemical Science, Journal Year: 2024, Volume and Issue: 15(10), P. 3711 - 3720

Published: Jan. 1, 2024

An efficient glycosylation reaction utilizing a meticulously designed thioglycoside has been developed. The well-established protocol was demonstrated in the total synthesis of TD139 and one-pot assembly E. coli O33 antigen tetrasaccharide.

Language: Английский

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Mirror-image cyclodextrins

Nature Synthesis, Journal Year: 2024, Volume and Issue: 3(6), P. 698 - 706

Published: March 28, 2024

Language: Английский

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Chemical synthesis of polysaccharides

Current Opinion in Chemical Biology, Journal Year: 2022, Volume and Issue: 69, P. 102154 - 102154

Published: May 5, 2022

Language: Английский

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Recent advances in stereoselective 1,2-cis-O-glycosylations

Frontiers in Chemistry, Journal Year: 2022, Volume and Issue: 10

Published: Aug. 19, 2022

For the stereoselective assembly of bioactive glycans with various functions, 1,2-

Language: Английский

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Highly stereoselective α-glycosylation with GalN₃ donors enabled collective synthesis of mucin-related tumor associated carbohydrate antigens

Chemical Science, Journal Year: 2024, Volume and Issue: 15(17), P. 6552 - 6561

Published: Jan. 1, 2024

Collective synthesis of mucin-related tumor associated carbohydrate antigens has been achieved via this new α-glycosylation method with GalN 3 donors, which features mild conditions, broad substrate scope, high yields and stereoselectivities.

Language: Английский

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Total Synthesis of Nona-decasaccharide Motif from Ganoderma sinense Polysaccharide Enabled by Modular and One-Pot Stereoselective Glycosylation Strategy

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(25), P. 17446 - 17455

Published: June 11, 2024

Polysaccharides from a medicinal fungus Ganoderma sinense represent important and adjunctive therapeutic agents for treating various diseases, including leucopenia hematopoietic injury. However, the synthetic accessibility to long, branched, complicated carbohydrates chains polysaccharides remains challenging task in chemical synthesis. Here, we report modular synthesis of nona-decasaccharide motif polysaccharide GSPB70-S with diverse biological activities first time through one-pot stereoselective glycosylation strategy on basis glycosyl ortho-(1-phenyvinyl)benzoates, which not only sped up but also reduced waste avoided aglycones transfer issues inherent thioglycosides. The route highlights following key steps: (1) preactivation-based highly constructions several 1,2-cis-glycosidic linkages, three α-d-GlcN-(1 → 4) linkages one α-d-Gal-(1 bond via reagent N-methyl-N-phenylformamide modulation; (2) orthogonal assembly 1,2-trans-glycosidic linear branched glycans fragments by strategic combinations N-phenyltrifluoroacetimidates, ortho-alkynylbenzoates, ortho-(1-phenyvinyl)benzoates; (3) final [1 × 4 + 15] Yu efficient target. Additionally, shorter sequences 4-mer, 5-mer, 6-mer are prepared structure–activity relationship studies. present work shows that this can offer reliable effective means streamline complex many bonds.

Language: Английский

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Dendrobium huoshanense C.Z.Tang et S.J.Cheng: A Review of Its Traditional Uses, Phytochemistry, and Pharmacology

Frontiers in Pharmacology, Journal Year: 2022, Volume and Issue: 13

Published: July 12, 2022

Dendrobium huoshanense , a traditional medicinal and food homologous plant, belongs to the family Orchidaceae has long history of use. It is reported that stem D. variety bioactive ingredients such as polysaccharides, flavonoids, sesquiterpenes, phenols, etc. These make remarkable for its pharmacological effects on anti-tumor, immunomodulation, hepatoprotective, antioxidant, anticataract activities. In recent years, rich activities have attracted extensive attention. However, there no systematic review focusing chemical compositions . Therefore, present aims summarize current research This study provides valuable references promising ideas further investigations

Language: Английский

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Chemical Synthesis of the Highly Sterically Hindered Core Undecasaccharide of Helicobacter pylori Lipopolysaccharide for Antigenicity Evaluation with Human Serum

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(32), P. 14535 - 14547

Published: Aug. 8, 2022

Helicobacter pylori, listed as a human carcinogen by the Department of Health and Human Services, colonizes gastric mucosa more than half world's population. The individuals infected with H. pylori have high risk to develop chronic gastritis, peptic ulcers, even cancer. conserved core structure lipopolysaccharide (LPS) has been regarded promising candidate for development glycoconjugate vaccine targeting multiple serotypes. Here, we report total synthesis undecasaccharide LPS its subunit antigens. match mismatch between glycosyl donor acceptor caused inert hydroxyl groups were addressed judicious choice orthogonal protection strategies glycosylation conditions. A combination acyl remote participation solvent effects applied selective formation five 1,2-cis-glucosidic bonds. steric hindrance induced carbon sugars trinacriform architecture required that was synthesized through finely tuned linear assembly [2 + (1 (3 3))))] rather convergent strategies. An antigenicity evaluation using glycan microarrays showed an α-(1 → 6)-glucan trisaccharide is recognized IgG antibodies in sera pylori-infected patients. phosphate group inner key epitope very important recognition. These findings are step toward designing carbohydrate-based vaccines against pylori.

Language: Английский

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