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A 3,4-trans-fused cyclic protecting group facilitates ?-selective catalytic synthesis of 2-deoxyglycosides.

ABSTRACT: A practical approach has been developed to convert glucals and rhamnals into disaccharides or glycoconjugates with high ?-selectivity and yields (77-97%) using a trans-fused cyclic 3,4-O-disiloxane protecting group and TsOH?H2O (1?mol%) as a catalyst. Control of the anomeric selectivity arises from conformational locking of the intermediate oxacarbenium cation. Glucals outperform rhamnals because the C6 side-chain conformation augments the selectivity.

SUBMITTER: Balmond EI

PROVIDER: S-EPMC4499252 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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A 3,4-trans-fused cyclic protecting group facilitates α-selective catalytic synthesis of 2-deoxyglycosides.

Balmond Edward I EI Benito-Alifonso David D Coe Diane M DM Alder Roger W RW McGarrigle Eoghan M EM Galan M Carmen MC

Angewandte Chemie (International ed. in English) 20140620 31

A practical approach has been developed to convert glucals and rhamnals into disaccharides or glycoconjugates with high α-selectivity and yields (77-97%) using a trans-fused cyclic 3,4-O-disiloxane protecting group and TsOH⋅H2O (1 mol%) as a catalyst. Control of the anomeric selectivity arises from conformational locking of the intermediate oxacarbenium cation. Glucals outperform rhamnals because the C6 side-chain conformation augments the selectivity. ...[more]

PMID: 24953049

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