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Enantioselective Total Syntheses of (+)-Fendleridine and (+)-Acetylaspidoalbidine.

ABSTRACT: Enantioselective syntheses of hexacyclic aspidoalbidine alkaloids (+)-fendleridine (2) and (+)-acetylaspidoalbidine (3) are described. These syntheses feature an asymmetric decarboxylative allylation and photocyclization of a highly substituted enaminone. Also, the synthesis highlights the formation of a C19-hemiaminal ether via a reduction/condensation/intramolecular cyclization cascade with the C21-alcohol. The present synthesis provides convenient access to the aspidoalbidine hexacyclic alkaloid family in an efficient manner.

SUBMITTER: Ghosh AK

PROVIDER: S-EPMC6594018 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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Enantioselective Total Syntheses of (+)-Fendleridine and (+)-Acetylaspidoalbidine.

Ghosh Arun K AK Born Joshua R JR Kassekert Luke A LA

The Journal of organic chemistry 20190402 9

Enantioselective syntheses of hexacyclic aspidoalbidine alkaloids (+)-fendleridine (2) and (+)-acetylaspidoalbidine (3) are described. These syntheses feature an asymmetric decarboxylative allylation and photocyclization of a highly substituted enaminone. Also, the synthesis highlights the formation of a C19-hemiaminal ether via a reduction/condensation/intramolecular cyclization cascade with the C21-alcohol. The present synthesis provides convenient access to the aspidoalbidine hexacyclic alkal ...[more]

PMID: 30939004

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