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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]

The development of highly efficient metal‐free carbon electrocatalysts for the oxygen reduction reaction (ORR) is one very promising strategy for the exploitation and commercialization of renewable and clean energy, but this still remains a significant challenge. Herein, we demonstrate a facile approach to prepare three‐dimensional (3D) N‐doped carbon with a sp3/sp2 carbon interface derived from ionic liquids via a simple pyrolysis process. The tunable hybrid sp3 and sp2 carbon composition and pore structures stem from the transformation of ionic liquids to polymerized organics and introduction of a Co metal salt. Through tuning both composition and pores, the 3D N‐doped nanocarbon with a high sp3/sp2 carbon ratio on the surface exhibits a superior electrocatalytic performance for the ORR compared to that of the commercial Pt/C in Zn–air batteries. Density functional theory calculations suggest that the improved ORR performance can be ascribed to the existence of N dopants at the sp3/sp2 carbon interface, which can lower the theoretical overpotential of the ORR. [ABSTRACT FROM AUTHOR]

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]