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Stereoselective Synthesis of ?- and ?-l-Ara4N Glycosyl H-Phosphonates and a Neoglycoconjugate Comprising Glycosyl Phosphodiester Linked ?-l-Ara4N.

ABSTRACT: Stereoselective synthesis of variably protected ?- and ?-l-Ara4N glycosyl H-phosphonates as key intermediates in the syntheses of ?-l-Ara4N-modified LPS structures and ?-l-Ara4N-containing biosynthetic precursors is reported. A facile one-pot approach toward ?-l-Ara4N glycosyl H-phosphonates includes anomeric deallylation of protected 4-azido ?-l-Ara4N via terminal olefin isomerization followed by ozonolysis and methanolysis of formyl groups to furnish exclusively ?-configured lactols that are phosphitylated with retention of configuration. The carbohydrate epitope of ?-l-Ara4N-modified Lipid A, ?GlcN(1?6)?GlcN(1?P?1)?-l-Ara4N, was stereoselectively synthesized and linked to maleimide-activated bovine serum albumin.

SUBMITTER: Hollaus R

PROVIDER: S-EPMC5223274 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Stereoselective Synthesis of α- and β-l-Ara4N Glycosyl H-Phosphonates and a Neoglycoconjugate Comprising Glycosyl Phosphodiester Linked β-l-Ara4N.

Hollaus Ralph R Kosma Paul P Zamyatina Alla A

Organic letters 20161223 1

Stereoselective synthesis of variably protected α- and β-l-Ara4N glycosyl H-phosphonates as key intermediates in the syntheses of β-l-Ara4N-modified LPS structures and α-l-Ara4N-containing biosynthetic precursors is reported. A facile one-pot approach toward β-l-Ara4N glycosyl H-phosphonates includes anomeric deallylation of protected 4-azido β-l-Ara4N via terminal olefin isomerization followed by ozonolysis and methanolysis of formyl groups to furnish exclusively β-configured lactols that are p ...[more]

PMID: 28009171

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