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Synthesis of zwitterionic 1,1'-glycosylphosphodiester: a partial structure of galactosamine-modified Francisella lipid A.

ABSTRACT: Synthesis of a "double glycosidic" phosphodiester comprising anomeric centers of two 2-amino-2-deoxy-sugars is reported. The carbohydrate epitope of Francisella lipid A modified with ?-d-galactosamine at the anomerically linked phosphate has been stereoselectively prepared and coupled to maleimide-activated bovine serum albumin via an amide-linked thiol-terminated spacer group. H-Phosphonate and phosphoramidite approaches have been explored for the coupling of 4,6-DTBS-2-azido-protected GalN lactol and peracetylated spacer-equipped reducing ?GlcN(1?6)GlcN disaccharide via phosphodiester linkage. Deprotection conditions preserving the integrity of the labile glycosidic zwitterionic phosphodiester were elaborated.

SUBMITTER: Baum D

PROVIDER: S-EPMC4106266 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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Synthesis of zwitterionic 1,1'-glycosylphosphodiester: a partial structure of galactosamine-modified Francisella lipid A.

Baum David D Kosma Paul P Zamyatina Alla A

Organic letters 20140708 14

Synthesis of a "double glycosidic" phosphodiester comprising anomeric centers of two 2-amino-2-deoxy-sugars is reported. The carbohydrate epitope of Francisella lipid A modified with α-d-galactosamine at the anomerically linked phosphate has been stereoselectively prepared and coupled to maleimide-activated bovine serum albumin via an amide-linked thiol-terminated spacer group. H-Phosphonate and phosphoramidite approaches have been explored for the coupling of 4,6-DTBS-2-azido-protected GalN lac ...[more]

PMID: 25003818

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