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Allyl Cyanate/Isocyanate Rearrangement in Glycals: Stereoselective Synthesis of 1-Amino and Diamino Sugar Derivatives.

ABSTRACT: The [3,3]-sigmatropic allyl cyanate/isocyanate rearrangement of glycals in the presence of O-, N-, and C-nucleophiles afforded ?-N-glucosyl and galactosyl carbamates, ureas, and amides in good yields. The unsaturated products were elaborated to N-glycosides by dihydroxylation, to 1,3-diaminosugars by tethered aminohydroxylation, or to 1,2-diaminosugars by iteration of the sigmatropic rearrangement. This metal-free methodology represents an excellent and general method for the stereoselective synthesis of N-glycosides and diamino sugars with complete transmission of stereochemical information.

SUBMITTER: Mirabella S

PROVIDER: S-EPMC7735751 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Allyl Cyanate/Isocyanate Rearrangement in Glycals: Stereoselective Synthesis of 1-Amino and Diamino Sugar Derivatives.

Mirabella Stefania S Petrucci Giulia G Faggi Cristina C Matassini Camilla C Cardona Francesca F Goti Andrea A

Organic letters 20201104 22

The [3,3]-sigmatropic allyl cyanate/isocyanate rearrangement of glycals in the presence of O-, N-, and C-nucleophiles afforded β-N-glucosyl and galactosyl carbamates, ureas, and amides in good yields. The unsaturated products were elaborated to N-glycosides by dihydroxylation, to 1,3-diaminosugars by tethered aminohydroxylation, or to 1,2-diaminosugars by iteration of the sigmatropic rearrangement. This metal-free methodology represents an excellent and general ...[more]

PMID: 33147974

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