Structural analysis of stereoselective galactose pyruvylation toward the synthesis of bacterial capsular polysaccharides

• Tsun-Yi Chiang,
• Mei-Huei Lin,
• Chun-Wei Chang,
• Jinq-Chyi Lee and
• Cheng-Chung Wang

Beilstein J. Org. Chem. 2025, 21, 1671–1677, doi:10.3762/bjoc.21.131

• successfully obtained. Subsequently, the compound was used for the synthesis of zwitterionic polysaccharide A1 (PS A1) precursor, and a clear structural elucidation was applied by using nuclear magnetic resonance and X-ray. Keywords: carbohydrates; capsular polysaccharides; diastereochemistry; glycosylation

• -studied and are considered good candidates for drug development [1][6]. The synthesis of bacterial capsular polysaccharides, particularly in the installation of the pyruvate ketal on galactose, presents significant challenges. Owing to pyruvate ketals are considered immunogenic, non carbohydrate

Total synthesis of the O-antigen repeating unit of Providencia stuartii O49 serotype through linear and one-pot assemblies

• Tanmoy Halder and
• Somnath Yadav

Beilstein J. Org. Chem. 2021, 17, 2915–2921, doi:10.3762/bjoc.17.199

• Tanmoy Halder Somnath Yadav Department of Chemistry, Indian Institute of Technology (ISM), Dhanbad, 826004, Jharkhand, India 10.3762/bjoc.17.199 Abstract Capsular polysaccharides of pathogenic bacteria have been reported to be effective vaccines against diseases caused by them. Providencia

Convergent synthesis of the pentasaccharide repeating unit of the biofilms produced by Klebsiella pneumoniae

• Arin Gucchait,
• Angana Ghosh and
• Anup Kumar Misra

Beilstein J. Org. Chem. 2019, 15, 431–436, doi:10.3762/bjoc.15.37

• -antigens [4]. The pathogenicity of K. pneumoniae relies on the structure of the capsular polysaccharides [5]. Besides a large number of polysaccharides present in the capsules, K. pneumoniae secrets a variety of polysaccharides which form biofilms for the protection of the organism from external agents [6

• ]. In addition, secreted polysaccharides from a particular strain also render pathogenicity of that organism. Since capsular polysaccharides of K. pneumoniae and polysaccharides secreted by it play an important role in the initial stage of infections [7], it is quite pertinent to develop therapeutics

• the oligosaccharide fragments corresponding to the capsular polysaccharides or polysaccharides secreted by the bacterial strains, is to develop effective synthetic strategies. The structure and glycosyl linkages of the monosaccharide units remain conserved in the synthesized oligosaccharides in

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

• Gram-positive bacterium that colonizes the upper respiratory tract and causes life-threatening pulmonary diseases as well as infections of the brain, the middle ear and the sinuses [1][2][3][4][5][6]. Twenty-three of the more than ninety S. pneumoniae serotypes, which differ in the capsular

• polysaccharides (CPS) that surround them, are responsible for about 90% of infections worldwide [7]. The licensed polysaccharide vaccine Pneumovax 23 contains serotype 12F but is not efficacious in young children or elderly people, those at highest risk. The carbohydrate conjugate vaccines Prevanar13™ and

Convergent synthesis of a tetrasaccharide repeating unit of the O-specific polysaccharide from the cell wall lipopolysaccharide of Azospirillum brasilense strain Sp7

• Pintu Kumar Mandal,
• Debashis Dhara and
• Anup Kumar Misra

Beilstein J. Org. Chem. 2014, 10, 293–299, doi:10.3762/bjoc.10.26

• macromolecules such as exopolysaccharides (EPS), lipopolysaccharides (LPS) and capsular polysaccharides (CPS), which influence their interactions with plants [13][14][15]. There are only a limited number of reports on structural studies of the LPS present in the cell wall of Azospirilla species despite their

Facile synthesis of nitrophenyl 2-acetamido-2-deoxy-α-D-mannopyranosides from ManNAc-oxazoline

• Karel Křenek,
• Petr Šimon,
• Lenka Weignerová,
• Barbora Fliedrová,
• Marek Kuzma and
• Vladimír Křen

Beilstein J. Org. Chem. 2012, 8, 428–432, doi:10.3762/bjoc.8.48

• capsular polysaccharides in Gram-negative bacteria. N-Acetyl-D-mannosamine (ManNAc) has been found to be, presumably, the strongest monosaccharidic ligand for the natural killer cells (NK-cells) activating protein NKR-P1 [1], and some ManNAc-containing oligosaccharides (e.g., GlcpNAc-β-(1→4)ManpNAc) have