Introduction of a human- and keyboard-friendly N-glycan nomenclature

• Friedrich Altmann,
• Johannes Helm,
• Martin Pabst and
• Johannes Stadlmann

Beilstein J. Org. Chem. 2024, 20, 607–620, doi:10.3762/bjoc.20.53

• . Noteworthy, the number of numeric figures gives the number of mannose residues in addition to the three of the core. The example (M6M3)M2 contains three numbers and hence describes a hexasaccharide (Figure 10). Plant and insect glycans This chapter arises from the authors´ long involvement with glycoproteins

Synthesis of protected precursors of chitin oligosaccharides by electrochemical polyglycosylation of thioglycosides

• Md Azadur Rahman,
• Kana Kuroda,
• Hirofumi Endo,
• Norihiko Sasaki,
• Tomoaki Hamada,
• Hiraku Sakai and
• Toshiki Nokami

Beilstein J. Org. Chem. 2022, 18, 1133–1139, doi:10.3762/bjoc.18.117

• thioglycosides as monomer is described. Oligosaccharides up to the hexasaccharide were synthesized under optimized reaction conditions. Further, a modified method enabled the synthesis of oligosaccharides up to the octasaccharide by repeating electrolysis with additional monomers. The mechanism of the

• V vs SCE) gave oligosaccharides up to hexasaccharide 6a, although the yield of pentasaccharide 5a (3%) and hexasaccharide 6a (1%) was very low. For thioglycoside 1b (Ar = 4-ClC6H4, Eox = 1.68 V vs SCE), the highest conversion (79%) and the highest yield of tetrasaccharide 4b (14%) were observed

• of oligosaccharides and/or trehalose pseudo-oligosaccharides, which were major byproducts at the elevated temperature, became stronger in the corresponding peaks of longer oligosaccharides, such as hexasaccharide 6a and heptasaccharide 7a. Proposed structures of byproducts of trisaccharide 3a

Progress and challenges in the synthesis of sequence controlled polysaccharides

• Giulio Fittolani,
• Theodore Tyrikos-Ergas,
• Denisa Vargová,
• Manishkumar A. Chaube and
• Martina Delbianco

Beilstein J. Org. Chem. 2021, 17, 1981–2025, doi:10.3762/bjoc.17.129

• , ranging from tri- to hexasaccharide, was obtained via iterative electrochemical assembly [266]. A solid-phase automated approach delivered β(1–6)-glucosamine hexasaccharide 87a and dodecasaccharide 87b (Scheme 13A) [267]. β(1–3)-Oligomer 90 was prepared as chitin mimetics (Scheme 13B). Despite the subtle

Unexpected loss of stereoselectivity in glycosylation reactions during the synthesis of chondroitin sulfate oligosaccharides

• Teresa Mena-Barragán,
• José L. de Paz and
• Pedro M. Nieto

Beilstein J. Org. Chem. 2019, 15, 137–144, doi:10.3762/bjoc.15.14

• temperature (−20 ºC), typical conditions for favoring the formation of the β-bond, increased the β-selectivity (1:4 α/β ratio) but also decreased the overall yield (50%). Similarly, a loss of β-selectivity was observed at the hexasaccharide stage (Scheme 7). Tetrasaccharide acceptor 20 was prepared from 19β

Preactivation-based chemoselective glycosylations: A powerful strategy for oligosaccharide assembly

• Weizhun Yang,
• Bo Yang,
• Sherif Ramadan and
• Xuefei Huang

Beilstein J. Org. Chem. 2017, 13, 2094–2114, doi:10.3762/bjoc.13.207

• , which has been covered in other reviews [23][42], has been applied to successful synthesis of a range of complex oligosaccharides including human milk oligosaccharides [45], an embryonic stem cell surface carbohydrate marker Lc4 [46], Globo-H hexasaccharide [47], and heparin-like oligosaccharides [48

• hexasaccharide 105 was prepared within 7 hours in an excellent overall yield of 47% from the sequential one-pot reaction of 101, 102, 103 and 104. Compared to the automated solid-phase synthesis of Globo-H [61], the solution-based preactivation-based synthesis gave a higher overall yield for glyco-assembly (47

• monosaccharide building blocks (106–108) led to the formation of hexasaccharide 109 in an excellent 63% yield in one pot on a gram scale (Scheme 19a). This is the largest number of glycosylation reactions that have been performed in one pot to date. Further iterative five-component one-pot glycosylation (111

Strategies toward protecting group-free glycosylation through selective activation of the anomeric center

• A. Michael Downey and
• Michal Hocek

Beilstein J. Org. Chem. 2017, 13, 1239–1279, doi:10.3762/bjoc.13.123

Total synthesis of a Streptococcus pneumoniae serotype 12F CPS repeating unit hexasaccharide

• Peter H. Seeberger,
• Claney L. Pereira and
• Subramanian Govindan

Beilstein J. Org. Chem. 2017, 13, 164–173, doi:10.3762/bjoc.13.19

• better immunological understanding of the epitopes that protect from bacterial infection requires defined oligosaccharides obtained by total synthesis. The key to the synthesis of the S. pneumoniae serotype 12F CPS hexasaccharide repeating unit that is not contained in currently used glycoconjugate

• ] strategy that was not successful due to steric constraints. The synthetic hexasaccharide is the starting point for further immunological investigations. Keywords: carbohydrate antigen; glycosylation; oligosaccharides; Streptococcus pneumoniae; total synthesis; Introduction Streptococcus pneumoniae is a

• antibodies that serve as tools for vaccine design [19] and for the detection of pathogenic bacteria such as Bacillus anthracis [20][21]. S. pneumoniae 12F CPS consists of hexasaccharide repeating units containing the [→4)-α-L-FucpNAc-(1→3)-β-D-GalpNAc-(1→4)-β-D-ManpNAcA-(1→] polysaccharide backbone with a

Synthesis of a hexasaccharide partial sequence of hyaluronan for click chemistry and more

• Marina Bantzi,
• Stephan Rigol and
• Athanassios Giannis

Beilstein J. Org. Chem. 2015, 11, 604–607, doi:10.3762/bjoc.11.67

• Abstract In the present work, the synthesis of a hexasaccharide partial sequence of hyaluronan equipped with a terminal azido moiety is reported. This hexasaccharide can be used for the attachment on surfaces by means of click chemistry and after suitable deprotection for biophysical studies. Keywords

• : azide; click chemistry; extracellular matrix; hexasaccharide; hyaluronan; multivalency; Introduction Much effort has been exerted during the last years to refine current knowledge about the biology of the extracellular matrix (ECM) [1]. While in the past, it was only regarded as a “space filler” among

• frame of a research project aiming the investigation of protein–GAG binding a convergent synthesis of a HA hexamer with a suitably modified aglycone is described herein. Results and Discussion The synthetic cascade to the desirable hexasaccharide 10 is presented in Scheme 1. Trichloroacetimidate 1 [20

Galactan synthesis in a single step via oligomerization of monosaccharides

• Marius Dräger and
• Amit Basu

Beilstein J. Org. Chem. 2014, 10, 2658–2663, doi:10.3762/bjoc.10.279

• early report describes the treatment of 2,3,4-tri-O-acetyl-glucopyranosyl bromide under Koenigs–Knorr conditions [12]. Products ranging from the β1→6 linked disaccharide to the hexasaccharide were obtained after separation, albeit in poor yields. A similar oligomerization of N-acetylglucosamine mediated

Expedient synthesis of 1,6-anhydro-α-D-galactofuranose, a useful intermediate for glycobiological tools

• Luciana Baldoni and
• Carla Marino

Beilstein J. Org. Chem. 2014, 10, 1651–1656, doi:10.3762/bjoc.10.172

• strategy, Ning and co-workers synthesized the β-(1→6)-linked hexasaccharide 7 [29], and Kiessling‘s group developed the synthesis of compounds 8.used for the characterization of GlfT2, one of the two galactofuranosyl transferases involved in the biosynthesis of D-Galf-containing molecules (Figure 2) [30

Synthesis of 4” manipulated Lewis X trisaccharide analogues

• Christopher J. Moore and
• France-Isabelle Auzanneau

Beilstein J. Org. Chem. 2012, 8, 1134–1143, doi:10.3762/bjoc.8.126

• yields. Keywords: chlorodeoxygalactose; fluorodeoxygalactose; Lewis X analogues; oligosaccharide synthesis; Introduction A glycolipid displaying the dimeric Lex hexasaccharide (dimLex) has been identified as a cancer associated carbohydrate antigen, particularly prevalent in colonic and liver

• ) have been shown to recognize this Lex antigenic determinant as it exists in the hexasaccharide [1][2][3][4][5][6]. Therefore, as our group embarks on the development of a therapeutic anticancer vaccine utilizing the Tumor Associated Carbohydrate Antigen (TACA) dimLex as a target, an important factor to

Convergent syntheses of Le^X analogues

• An Wang,
• Jenifer Hendel and
• France-Isabelle Auzanneau

Beilstein J. Org. Chem. 2010, 6, No. 17, doi:10.3762/bjoc.6.17

• ][4][5][6]. This tumor specific antigen consists of a hexasaccharide that displays the Lex trisaccharide antigen linked to O-3″ of the galactose residue of another Lex trisaccharide. Since it was first characterized [7][8], the Lex antigenic determinant, β-D-Galp(1,4)[α-LFucp(1,3)]-D-GlcNAcp, has been