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Cascade Metathesis Reactions for the Synthesis of Taxane and Isotaxane Derivatives.

ABSTRACT: Tricyclic isotaxane and taxane derivatives have been synthesized by a very efficient cascade ring-closing dienyne metathesis (RCDEYM) reaction, which formed the A and B rings in one operation. When the alkyne is present at C13 (with no neighboring gem-dimethyl group), the RCEDYM reaction leads to 14,15-isotaxanes 16?a,b and 18?b with the gem-dimethyl group on the A ring. If the alkyne is at the C11 position (and thus flanked by a gem-dimethyl group), RCEDYM reaction only proceeds in the presence of a trisubstituted olefin at C13, which disfavors the competing diene ring-closing metathesis reaction, to give the tricyclic core of Taxol 44.

SUBMITTER: Ma C

PROVIDER: S-EPMC4982030 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

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Cascade Metathesis Reactions for the Synthesis of Taxane and Isotaxane Derivatives.

Ma Cong C Letort Aurélien A Aouzal Rémi R Wilkes Antonia A Maiti Gourhari G Farrugia Louis J LJ Ricard Louis L Prunet Joëlle J

Chemistry (Weinheim an der Bergstrasse, Germany) 20160408 20

Tricyclic isotaxane and taxane derivatives have been synthesized by a very efficient cascade ring-closing dienyne metathesis (RCDEYM) reaction, which formed the A and B rings in one operation. When the alkyne is present at C13 (with no neighboring gem-dimethyl group), the RCEDYM reaction leads to 14,15-isotaxanes 16 a,b and 18 b with the gem-dimethyl group on the A ring. If the alkyne is at the C11 position (and thus flanked by a gem-dimethyl group), RCEDYM reaction only proceeds in the presence ...[more]

PMID: 27062670

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