Chemical Synthesis of β-l-Rhamnose Containing the Pentasaccharide Repeating Unit of the O-Specific Polysaccharide from a Halophilic Bacterium Halomonas ventosae RU5S2EL in the Form of Its 2-Aminoethyl Glycoside

Chemical synthesis of the pentasaccharide repeating unit of the O-specific polysaccharide from Escherichia coli O132 in the form of its 2-aminoethyl glycoside

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.15.249 ◽

2019 ◽

Vol 15 ◽

pp. 2563-2568

Author(s):

Debasish Pal ◽

Balaram Mukhopadhyay

Keyword(s):

Escherichia Coli ◽

Chemical Synthesis ◽

Building Blocks ◽

Protecting Group ◽

E Coli ◽

Specific Polysaccharide

The total chemical synthesis of the pentasaccharide repeating unit of the O-polysaccharide from E. coli O132 is accomplished in the form of its 2-aminoethyl glycoside. The 2-aminoethyl glycoside is particularly important as it allows further glycoconjugate formation utilizing the terminal amine without affecting the stereochemistry of the reducing end. The target was achieved through a [3 + 2] strategy where the required monosaccharide building blocks are prepared from commercially available sugars through rational protecting group manipulation. The NIS-mediated activation of thioglycosides was used extensively for the glycosylation reactions throughout.

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Chemical Synthesis of the Galacturonic Acid Containing Pentasaccharide Antigen of the O-Specific Polysaccharide ofVibrio choleraeO139 and Its Five Fragments

The Journal of Organic Chemistry ◽

10.1021/acs.joc.6b01019 ◽

2016 ◽

Vol 81 (15) ◽

pp. 6374-6394 ◽

Cited By ~ 4

Author(s):

Xiaowei Lu ◽

Pavol Kováč

Keyword(s):

Chemical Synthesis ◽

Galacturonic Acid ◽

Specific Polysaccharide

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Structure of the 4-O-[1-Carboxyethyl]-d-Mannose-Containing O-Specific Polysaccharide of a Halophilic Bacterium Salinivibrio sp. EG9S8QL

Marine Drugs ◽

10.3390/md19090508 ◽

2021 ◽

Vol 19 (9) ◽

pp. 508

Author(s):

Elena N. Sigida ◽

Ibrahim M. Ibrahim ◽

Maxim S. Kokoulin ◽

Hussein H. Abulreesh ◽

Khaled Elbanna ◽

...

Keyword(s):

Nmr Spectroscopy ◽

13C Nmr Spectroscopy ◽

Halophilic Bacterium ◽

Mild Acid Hydrolysis ◽

1H And 13C Nmr ◽

Specific Polysaccharide ◽

Lake Qarun ◽

Phenol Water ◽

Hydrolysis Of ◽

Mild Acid

The moderately halophilic strain Salinivibrio sp. EG9S8QL was isolated among 11 halophilic strains from saline mud (Emisal Salt Company, Lake Qarun, Fayoum, Egypt). The lipopolysaccharide was extracted from dried cells of Salinivibrio sp. EG9S8QL by the phenol–water procedure. The OPS was obtained by mild acid hydrolysis of the lipopolysaccharide and was studied by sugar analysis along with 1H and 13C NMR spectroscopy, including 1H,1H COSY, TOCSY, ROESY, 1H,13C HSQC, and HMBC experiments. The OPS was found to be composed of linear tetrasaccharide repeating units of the following structure: →2)-β-Manp4Lac-(1→3)-α-ManpNAc-(1→3)-β-Rhap-(1→4)-α-GlcpNAc-(1→, where Manp4Lac is 4-O-[1-carboxyethyl]mannose.

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