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Synthesis and photoinitiated thiol-ene reactions of exo-mannals - a new route to C-β-d-mannosyl derivatives.

ABSTRACT: Syntheses of acyl protected exo-mannal derivatives were developed starting from O-peracylated mannopyranoses via the corresponding anhydro-aldose tosylhydrazones under modified Bamford-Stevens conditions. The synthesis of analogous O-peralkylated (benzylated and isopropylenated) derivatives was carried out from pyranoid and furanoid mannonolactones using methylene transfer reagents. Photoinitiated thiol-ene additions of these exo-mannals resulted in the corresponding C-(mannopyranosyl/mannofuranosyl)methyl sulfides in medium to good yields with exclusive regio- and β(d) stereoselectivities.

SUBMITTER: Jozsef J

PROVIDER: S-EPMC9056834 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Synthesis and photoinitiated thiol-ene reactions of exo-mannals - a new route to C-β-d-mannosyl derivatives.

József János J Debreczeni Nóra N Eszenyi Dániel D Borbás Anikó A Juhász László L Somsák László L

RSC advances 20200922 57

Syntheses of acyl protected exo-mannal derivatives were developed starting from O-peracylated mannopyranoses via the corresponding anhydro-aldose tosylhydrazones under modified Bamford-Stevens conditions. The synthesis of analogous O-peralkylated (benzylated and isopropylenated) derivatives was carried out from pyranoid and furanoid mannonolactones using methylene transfer reagents. Photoinitiated thiol-ene additions of these exo-mannals resulted in the corresp ...[more]

PMID: 35514420

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