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Total Synthesis of (±)-Cis-Trikentrin B via Intermolecular 6,7-Indole Aryne Cycloaddition and Stille Cross-Coupling.

ABSTRACT: An efficient total synthesis of the annulated indole natural product (±)-cis-trikentrin B was accomplished by means of a regioselectively generated 6,7-indole aryne cycloaddition via selective metal-halogen exchange from a 5,6,7-tribromoindole. The unaffected C-5 bromine was subsequently used for a Stille cross-coupling to install the butenyl side chain and complete the synthesis. This strategy provides rapid access into the trikentrins and the related herbindoles, and represents another application of this methodology to natural products total synthesis. The required 5,6,7-indole aryne precursor was prepared using the Leimgruber-Batcho indole synthesis.

SUBMITTER: Chandrasoma N

PROVIDER: S-EPMC4179867 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

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Total Synthesis of (±)-Cis-Trikentrin B via Intermolecular 6,7-Indole Aryne Cycloaddition and Stille Cross-Coupling.

Chandrasoma Nalin N Brown Neil N Brassfield Allen A Nerurkar Alok A Suarez Susana S Buszek Keith R KR

Tetrahedron letters 20130201 8

An efficient total synthesis of the annulated indole natural product (±)-<i>cis</i>-trikentrin B was accomplished by means of a regioselectively generated 6,7-indole aryne cycloaddition <i>via</i> selective metal-halogen exchange from a 5,6,7-tribromoindole. The unaffected C-5 bromine was subsequently used for a Stille cross-coupling to install the butenyl side chain and complete the synthesis. This strategy provides rapid access into the trikentrins and the related herbindoles, and represents a ...[more]

PMID: 25278636

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