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Lipopolysaccharides from Bacteroides vulgatus represent interesting targets for the treatment of inflammatory bowel diseases. However, efficient access to long, branched and complex lipopolysaccharides remains challenging. Herein, we report the modular synthesis of a tridecasaccharide from Bacteroides vulgates through an orthogonal one‐pot glycosylation strategy based on glycosyl ortho‐(1‐phenylvinyl)benzoates, which avoids the issues of thioglycoside‐based one‐pot synthesis. Our approach also features: 1) 5,7‐O‐di‐tert‐butylsilylene‐directed glycosylation for stereoselective construction of the α‐Kdo linkage; 2) hydrogen‐bond‐mediated aglycone delivery for the stereoselective formation of β‐mannosidic bonds; 3) remote anchimeric assistance for stereoselective assembly of the α‐fucosyl linkage; 4) several orthogonal one‐pot synthetic steps and strategic use of orthogonal protecting groups to streamline oligosaccharide assembly; 5) convergent [1+6+6] one‐pot synthesis of the target. [ABSTRACT FROM AUTHOR]

Lipopolysaccharides from Bacteroides vulgatus represent interesting targets for the treatment of inflammatory bowel diseases. However, efficient access to long, branched and complex lipopolysaccharides remains challenging. Herein, we report the modular synthesis of a tridecasaccharide from Bacteroides vulgates through an orthogonal one‐pot glycosylation strategy based on glycosyl ortho‐(1‐phenylvinyl)benzoates, which avoids the issues of thioglycoside‐based one‐pot synthesis. Our approach also features: 1) 5,7‐O‐di‐tert‐butylsilylene‐directed glycosylation for stereoselective construction of the α‐Kdo linkage; 2) hydrogen‐bond‐mediated aglycone delivery for the stereoselective formation of β‐mannosidic bonds; 3) remote anchimeric assistance for stereoselective assembly of the α‐fucosyl linkage; 4) several orthogonal one‐pot synthetic steps and strategic use of orthogonal protecting groups to streamline oligosaccharide assembly; 5) convergent [1+6+6] one‐pot synthesis of the target. [ABSTRACT FROM AUTHOR]

A total synthesis of nonasaccharide repeating units and shorter sequences from Phellinus ribis glycans with strong immunostimulating activities was achieved by an orthogonal one-pot glycosylation strategy based on an N -phenyltrifluoroacetimidate glycosylation, a Yu glycosylation, and an ortho -(1-phenylvinyl)benzoate glycosylation. The issues inherent to thioglycosides-based orthogonal one-pot glycosylations, such as aglycone transfer, are eliminated by this one-pot glycosylation strategy, which streamlines the chemical synthesis of glycans. [ABSTRACT FROM AUTHOR]

Inside Cover: Modular Synthesis of a Tridecasaccharide Motif of Bacteroides vulgatus Lipopolysaccharides against Inflammatory Bowel Diseases through an Orthogonal One-Pot Glycosylation Strategy (Angew. Keywords: Anti-Inflammatory Activity; Lipopolysaccharides; Oligosaccharide Synthesis; Orthogonal One-Pot Glycosylation; Stereoselectivity EN Anti-Inflammatory Activity Lipopolysaccharides Oligosaccharide Synthesis Orthogonal One-Pot Glycosylation Stereoselectivity 1 1 1 05/16/23 20230522 NES 230522 B Lipopolysaccharides b from I Bacteroides vulgatus i represent interesting targets for the treatment of inflammatory bowel diseases. Anti-Inflammatory Activity, Lipopolysaccharides, Oligosaccharide Synthesis, Orthogonal One-Pot Glycosylation, Stereoselectivity. [Extracted from the article]

In their Research Article (e202301351), Guozhi Xiao and co-workers accomplished the first synthesis of a tridecasaccharide motif from I Bacteroides vulgatus i lipopolysaccharides by a strategy involving orthogonal one-pot glycosylation reactions based on glycosyl I ortho i -(1-phenylvinyl)benzoates, which avoided issues such as aglycone transfer and the unpleasant odor of thioglycoside-based orthogonal one-pot glycosylation. Anti-Inflammatory Activity, Lipopolysaccharides, Oligosaccharide Synthesis, Orthogonal One-Pot Glycosylation, Stereoselectivity Keywords: Anti-Inflammatory Activity; Lipopolysaccharides; Oligosaccharide Synthesis; Orthogonal One-Pot Glycosylation; Stereoselectivity EN Anti-Inflammatory Activity Lipopolysaccharides Oligosaccharide Synthesis Orthogonal One-Pot Glycosylation Stereoselectivity 1 1 1 05/16/23 20230522 NES 230522 B Lipopolysaccharides b from I Bacteroides vulgatus i represent interesting targets for the treatment of inflammatory bowel diseases. [Extracted from the article]

Ethnopharmacology relevance He-Ying-Qing-Re Formula (HF) is a formula modified from “Si-Miao-Yong-An Decoction”, a traditional Chinese medical classic emerged in the Qing dynasty and has been reported for treatment of vascular diseases. HF, containing 8 herbs, has been used in local hospital for decades as a complementary method for diabetic retinopathy (DR) with retinal vascular dysfunction. Clinical reports revealed HF could ameliorate vision defects, microaneurysms, hemorrhages and macular edema. The aim of this study is to investigate the anti-DR action of HF and its underlying mechanism experimentally. Methods Chromatographic fingerprinting of HF and rodent model of DR were established; hypoglycemic effect of HF was measured by fasting, random blood glucose and glucose tolerance test; vascular degeneration was measured by retinal digestion; blood-retina-barrier (BRB) permeability was assessed with Evans Blue leakage assay. Advanced glycation end products (AGEs) were measured in vitro and in vivo level; Migration of retinal vascular endothelial cells were determined by wound healing and transwell chamber assays; permeability of endothelial monolayer was monitored with dextran transport. AGEs-related proteins and signaling were measured with immunoblotting and immunohistochemistry. Results Chlorogenic acid, ferulic acid and arctin were identified as major components in HF; HF suppresses retinal vasculature degeneration and BRB permeability damage without significant inhibition on hyperglycemia; HF reduces in vitro and in vivo formation of AGEs and AGEs-induced migration as well as permeability of retinal vascular endothelial cells. Expression of tight junction proteins Zo-1 and Claudin-1 was increased while activation of AGEs receptor and downstream signaling Akt were suppressed upon HF treatment. Conclusions HF exhibits protective effect against diabetic retinopathy, which may be associated with inhibition on AGEs and recovery on endothelial dysfunction via modulation of tight junction and AGEs downstream signaling. [ABSTRACT FROM AUTHOR]