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Ring-Expansion Approaches for the Total Synthesis of Salimabromide.

ABSTRACT: We describe the evolution of a synthetic strategy for the construction of the marine polyketide salimabromide. Combining a bicyclo[3.1.0]hexan-2-one ring-expansion to build up a functionalized naphthalene and an unprecedented rearrangement/cyclization cascade, enabled synthesis of a dearomatized tricyclic subunit of the target compound. Alternatively, an intramolecular ketiminium [2+2]-cycloaddition and subsequent Baeyer-Villiger ring-expansion gave access to the sterically encumbered architecture of salimabromide. Sequential oxidation of the carbon framework finally enabled the total synthesis of this unusual natural product.

SUBMITTER: Schmid M

PROVIDER: S-EPMC6544523 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Ring-Expansion Approaches for the Total Synthesis of Salimabromide.

Schmid Matthias M Grossmann Adriana S AS Mayer Peter P Müller Thomas T Magauer Thomas T

Tetrahedron 20190309 24

We describe the evolution of a synthetic strategy for the construction of the marine polyketide salimabromide. Combining a bicyclo[3.1.0]hexan-2-one ring-expansion to build up a functionalized naphthalene and an unprecedented rearrangement/cyclization cascade, enabled synthesis of a dearomatized tricyclic subunit of the target compound. Alternatively, an intramolecular ketiminium [2+2]-cycloaddition and subsequent Baeyer-Villiger ring-expansion gave access to the sterically encumbered architectu ...[more]

PMID: 31160829

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