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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Convergent synthesis of the pentasaccharide repeating unit of the cell wall K116 capsular polysaccharide of Acinetobacter baumannii

Tetrahedron, Journal Year: 2025, Volume and Issue: unknown, P. 134537 - 134537

Published: Feb. 1, 2025

Language: Английский

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Zinc(ii)-mediated stereoselective construction of 1,2-cis 2-azido-2-deoxy glycosidic linkage: assembly of Acinetobacter baumannii K48 capsular pentasaccharide derivative

Chemical Science, Journal Year: 2024, Volume and Issue: 15(32), P. 12889 - 12899

Published: Jan. 1, 2024

The capsular polysaccharide (CPS) is a major virulence factor of the pathogenic Acinetobacter baumannii and promising target for vaccine development.

Language: Английский

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One-Pot Assembly of Octasaccharide Motif from Cranberry Arabinoxyloglucan Oligosaccharides

Synlett, Journal Year: 2024, Volume and Issue: unknown

Published: June 30, 2024

Abstract Chemical synthesis of octasaccharide motif from cranberry arabinoxyloglucan oligosaccharides with antiadhesion activities has been achieved for the first time. Synthetic approach highlights following features: 1) stereoselective constructions 1,2-cis-Xyl bonds via combination reagent modulation and remote participation; 2) modular [1+3+1+3] orthogonal one-pot assembly target on basis glycosyl ortho-(1-phenylvinyl)benzoate, which avoids issues such as aglycone transfer associated glycosylation based thioglycosides.

Language: Английский

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Chemoenzymatic Synthesis of Common Legionaminic Acid−Containing Pentasaccharide of Capsular Polysaccharides from Acinetobacter baumanniiK27 and K44^†

Chinese Journal of Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 16, 2024

Comprehensive Summary Acinetobacter baumannii infections pose a great threat to public health owing upsurging antibiotic resistance. Capsular polysaccharides (CPS) are major virulence determinants of pathogenic bacteria and have attracted much attention as potential targets for vaccine development. However, the obtainability structurally well‐defined CPS‐related oligosaccharides remains challenging. Herein, we report an efficient chemoenzymatic strategy first total synthesis common CPS pentasaccharide repeating unit K27 K44, containing difficult‐to‐construct α‐linked 5,7‐di‐ N ‐acetyllegionaminic acid (Leg5,7Ac 2 ) residue. The chemical branched tetrasaccharide precursor was accomplished by flexible orthogonal protecting‐group manipulations stereocontrolled glycosylations. Furthermore, enzyme‐catalyzed stereoselective installment legionaminic residue into tetrasaccharide, using one‐pot multienzyme (OPME) system produce sugar nucleotide CMP‐Leg5,7diN 3 subsequent α2,6‐sialyltransferase‐catalyzed glycosylation, achieved synthesize pentasaccharide.

Language: Английский

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Chemical synthesis of rhynchosporosides

Journal of Carbohydrate Chemistry, Journal Year: 2024, Volume and Issue: unknown, P. 1 - 10

Published: Oct. 11, 2024

Chemical synthesis of rhynchosporosides that cause scald diseases in barley has been summarized this review. The features two different strategies, namely, two-stage activation and one-pot glycosylation. Comparing with the stepwise synthesis, assembly strategy based on glycosyl ortho-(1-phenylvinyl)benzoates can highly streamline carbohydrates avoiding such problems as aglycone transfer associated traditional glycosylation thioglycosides.

Language: Английский

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