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Enantioselective Synthesis of the Tricyclic Core of FR901483 Featuring a Rh-Catalyzed [2+2+2] Cycloaddition.

ABSTRACT: An efficient approach to the tricyclic framework of FR901483 is described. The sequence features a [3, 3]-sigmatropic rearrangement of a cyanate into an isocyanate, followed by its subsequent asymmetric rhodium-catalyzed [2+2+2] cycloaddition with a terminal alkyne for the synthesis of the indolizidine core. The aza-tricyclic core is completed using an intramolecular benzoin reaction to close the last ring of the natural product. Through a model study of the key cycloaddition, we evaluated the impact of different substituents on the tether of the alkenyl isocyanate.

SUBMITTER: Perreault S

PROVIDER: S-EPMC4263289 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Enantioselective Synthesis of the Tricyclic Core of FR901483 Featuring a Rh-Catalyzed [2+2+2] Cycloaddition.

Perreault Stéphane S Rovis Tomislav T

Synthesis 20130101 6

An efficient approach to the tricyclic framework of FR901483 is described. The sequence features a [3, 3]-sigmatropic rearrangement of a cyanate into an isocyanate, followed by its subsequent asymmetric rhodium-catalyzed [2+2+2] cycloaddition with a terminal alkyne for the synthesis of the indolizidine core. The <i>aza</i>-tricyclic core is completed using an intramolecular benzoin reaction to close the last ring of the natural product. Through a model study of the key cycloaddition, we evaluate ...[more]

PMID: 25506094

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