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Total Synthesis of Salimabromide: A Tetracyclic Polyketide from a Marine Myxobacterium.

ABSTRACT: Salimabromide is an antibiotic polyketide that was previously isolated from the obligate marine myxobacterium Enhygromyxa salina, and its densely functionalized and conformationally rigid tetracyclic framework is unprecedented in nature. Herein we report the first chemical synthesis of the target structure by employing a series of well-orchestrated, robust transformations, highlighted by an acid-promoted, powerful Wagner-Meerwein rearrangement/Friedel-Crafts cyclization sequence to forge the two adjacent quaternary carbon centers embedded in the tetrahydronaphthalene. A high-yielding ketiminium mediated [2+2]-cycloaddition was also utilized for the simultaneous construction of the remaining three stereocenters.

SUBMITTER: Schmid M

PROVIDER: S-EPMC6061937 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Total Synthesis of Salimabromide: A Tetracyclic Polyketide from a Marine Myxobacterium.

Schmid Matthias M Grossmann Adriana S AS Wurst Klaus K Magauer Thomas T

Journal of the American Chemical Society 20180702 27

Salimabromide is an antibiotic polyketide that was previously isolated from the obligate marine myxobacterium Enhygromyxa salina, and its densely functionalized and conformationally rigid tetracyclic framework is unprecedented in nature. Herein we report the first chemical synthesis of the target structure by employing a series of well-orchestrated, robust transformations, highlighted by an acid-promoted, powerful Wagner-Meerwein rearrangement/Friedel-Crafts cyclization sequence to forge the two ...[more]

PMID: 29953216

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