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Diastereoselective nitrenium ion-mediated cyclofunctionalization: total synthesis of (+)-castanospermine.

ABSTRACT: The asymmetric total synthesis of the ?-glucosidase inhibitor (+)-castanospermine is reported. The central theme in our approach to this polyhydroxylated alkaloid is the simultaneous generation of the piperidine ring and the C-1/8a erythro stereodiad through the diastereoselective, oxamidation of an unsaturated O-alkyl hydroxamate. This process is believed to proceed sequentially via singlet acylnitrenium and aziridinium ion intermediates.

SUBMITTER: Bowen EG

PROVIDER: S-EPMC2980585 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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Diastereoselective nitrenium ion-mediated cyclofunctionalization: total synthesis of (+)-castanospermine.

Bowen Edward G EG Wardrop Duncan J DJ

Organic letters 20101021 22

The asymmetric total synthesis of the α-glucosidase inhibitor (+)-castanospermine is reported. The central theme in our approach to this polyhydroxylated alkaloid is the simultaneous generation of the piperidine ring and the C-1/8a erythro stereodiad through the diastereoselective, oxamidation of an unsaturated O-alkyl hydroxamate. This process is believed to proceed sequentially via singlet acylnitrenium and aziridinium ion intermediates. ...[more]

PMID: 20964285

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