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A Highly Stereoselective, Efficient, and Scalable Synthesis of the C(1)-C(9) Fragment of the Epothilones.

ABSTRACT: A second-generation synthesis of the C(1)-C(9) fragment of the epothilones is reported. The key tandem intramolecular silylformylation/crotylsilylation/"aprotic" Tamao oxidation sequence has been redeveloped as a stepwise intermolecular variant, allowing excellent levels of diastereoselectivity in the crotylation step and proceeds in 50% overall yield on gram scale. An improved synthesis of the homopropargyl alcohol starting material is also described, which proceeds in four steps and >99% ee from inexpensive starting materials and is amenable to multigram scales.

SUBMITTER: Foley CN

PROVIDER: S-EPMC4811194 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature

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A Highly Stereoselective, Efficient, and Scalable Synthesis of the C(1)-C(9) Fragment of the Epothilones.

Foley Corinne N CN Leighton James L JL

Organic letters 20151112 23

A second-generation synthesis of the C(1)-C(9) fragment of the epothilones is reported. The key tandem intramolecular silylformylation/crotylsilylation/"aprotic" Tamao oxidation sequence has been redeveloped as a stepwise intermolecular variant, allowing excellent levels of diastereoselectivity in the crotylation step and proceeds in 50% overall yield on gram scale. An improved synthesis of the homopropargyl alcohol starting material is also described, which proceeds in four steps and >99% ee fr ...[more]

PMID: 26561788

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