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Keywords: 2-Deoxyglycosides; Bromine Radical; Intermolecular Hydroetherification; Photoreaction; Stereoselectivity EN 2-Deoxyglycosides Bromine Radical Intermolecular Hydroetherification Photoreaction Stereoselectivity 1 1 1 05/05/22 20220509 NES 220509 B Sichtbares Licht b vermittelt die iterative Synthese von 2-Desoxyoligosacchariden, über die De-Cai Xiong, Xin-Shan Ye und Mitarbeiter in ihrem Forschungsartikel berichten (e202114726). Innentitelbild: Iterative Synthesis of 2-Deoxyoligosaccharides Enabled by Stereoselective Visible-Light-Promoted Glycosylation (Angew. 2-Deoxyglycosides, Bromine Radical, Intermolecular Hydroetherification, Photoreaction, Stereoselectivity. [Extracted from the article]

2-Deoxyglycosides, Bromine Radical, Intermolecular Hydroetherification, Photoreaction, Stereoselectivity The rapid constructions of oligosaccharides, 20-mer deoxyglycan, and digoxin are facilitated by a bromide-based hydrogen species through an electron transfer process. Keywords: 2-Deoxyglycosides; Bromine Radical; Intermolecular Hydroetherification; Photoreaction; Stereoselectivity EN 2-Deoxyglycosides Bromine Radical Intermolecular Hydroetherification Photoreaction Stereoselectivity 1 1 1 05/05/22 20220509 NES 220509 B A visible-light-promoted b iterative synthesis of 2-deoxyoligosaccharides is reported by De-Cai Xiong, Xin-Shan Ye, and co-workers in their Research Article (e202114726). [Extracted from the article]

With the booming development of glycobiology and glycochemistry, more and more structures of tumor-associated carbohydrate antigens (TACAs) are identified. Their broad expression and high specificity in cancer make them important targets to develop cancer vaccines or immunotherapies. However, most of the TACAs are T cell-independent antigens, they cannot elicit a powerful enough immune response to prevent or treat cancer. Immunotolerance and immunosuppression are more easily induced due to their endogenous properties and the declining immunity of the patients. This review summarizes the recent efforts to overcome these obstacles: coupling the carbohydrate antigens to proper carriers such as proteins or some small molecule carriers, and chemically modifying the structures of the TACAs to enhance the immunogenicity of TACAs and break the immunotolerance. [ABSTRACT FROM AUTHOR]

Abstract: Ganglioside GM3 and its derivatives have many important biological functions. Using diethyl phosphite protected sialic acid as glycosyl donor and 3,2′,3′,4′-unprotected lactose as glycosyl acceptor, the sialic acid-containing trisaccharide was assembled with excellent anomeric stereoselectivity. The trisaccharide was further coupled with ceramide precursor to yield sphingosine 1. Based on this key intermediate, two different series of N-modified GM3 analogues with modifications on either the nitrogen of sialic acid residue or the nitrogen of ceramide moiety and GM3 itself were synthesized smoothly. [Copyright &y& Elsevier]

Abstract: The repeating GalpNAc-α-(1→4)-GalpNAc unit is part of a series of essential structures that can be found in many important biomolecules such as the glycoproteins and the O-antigenic polysaccharides of clinically important bacterial strains. In this paper, we describe an exclusive α-selective glycosylation reaction, using a 4,6-di-O-tert-butyldimethylsilyl-N-acetyloxazolidinone-protected thioglycoside as the glycosyl donor, under pre-activation conditions, with only half amount of the promoter, providing the product GalpNAc-α-(1→4)-GalpNAc in high isolated yield. This reaction can be also applied to increasing the length of the repeating structure, which is of significant use in further synthesis of branched or linear oligosaccharides. [ABSTRACT FROM AUTHOR]

An efficient preactivation protocol for the highly α-stereo�selective glycosylation of 2-deoxy- and 2,6-dideoxysugars has been developed using acetyl-protected 2-deoxy- and 2,6-dideoxythioglycosides as glycosyl donors. The approach allows a wide range of glycosyl acceptors and donors to be used. [ABSTRACT FROM AUTHOR]

NaHSO4�SiO2 was used as an efficient heterogeneous catalyst for both the formation and the cleavage of benzylidene �acetals. This catalyst is compatible with many functional or protective groups. Under different solvent systems, either the formation or the cleavage of benzylidene acetals was carried out smoothly in �excellent yields and with good chemoselectivity. [ABSTRACT FROM AUTHOR]

The increased awareness of the central role of RNA has led to realization that RNA, as structural and functional information accumulation, is also drug target to small molecular therapy. Aminoglycosides are a group of well-known antibiotics, which function through binding to specific sites in prokaryotic ribosomal RNA (rRNA) and affecting the fidelity of protein synthesis. Unfortunately, their clinical practice has been curtailed by toxicity and rapid increasing number of resistant strains. Therefore, it is highly desirable to design new modified aminoglycosides that will overcome the undesirable properties of natural occurring aminoglycosides. On the other hand, aminoglycosides as potential antiviral (HIV) agents were also reported. Herein, we survey the current efforts to develop new aminoglycoside derivatives with modification and reconstruction on each sugar ring and review the latest advances in structure-activity relationships (SAR). © 2006 Wiley Periodicals, Inc. Med Res Rev, 27, No. 3, 279-316, 2007 [ABSTRACT FROM AUTHOR]