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A convergent total synthesis of ouabagenin.

ABSTRACT: A convergent total synthesis of ouabagenin, an aglycon of cardenolide glycoside ouabain, was achieved by assembly of the AB-ring, D-ring and butenolide moieties. The multiply oxygenated cis-decalin structure of the AB-ring was constructed from (R)-perillaldehyde through the Diels-Alder reaction and sequential oxidations. The intermolecular acetal formation of the AB-ring and D-ring fragments, and combination of the intramolecular radical and aldol reactions, assembled the requisite steroidal skeleton in a stereoselective fashion. Finally, stereoselective installation of the C17-butenolide via the Stille coupling and hydrogenation led to ouabagenin.

SUBMITTER: Mukai K

PROVIDER: S-EPMC5490423 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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A convergent total synthesis of ouabagenin.

Mukai Ken K Kasuya Satoshi S Nakagawa Yuki Y Urabe Daisuke D Inoue Masayuki M

Chemical science 20150330 6

A convergent total synthesis of ouabagenin, an aglycon of cardenolide glycoside ouabain, was achieved by assembly of the AB-ring, D-ring and butenolide moieties. The multiply oxygenated <i>cis</i>-decalin structure of the AB-ring was constructed from (<i>R</i>)-perillaldehyde through the Diels-Alder reaction and sequential oxidations. The intermolecular acetal formation of the AB-ring and D-ring fragments, and combination of the intramolecular radical and aldol reactions, assembled the requisite ...[more]

PMID: 28706702

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