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A concise synthetic route to the stereotetrad core of the briarane diterpenoids.

ABSTRACT: A concise synthesis (under 10 steps) of the stereotetrad core of the briarane diterpenoids is reported. This approach harnesses the unique reactivity of salicylate ester derived 2,5-cyclohexadienones to quickly build complexity. In particular, a highly diastereoselective acetylide conjugate addition/?-ketoester alkylation sequence was used to set the relative configuration of the C1 (quaternary) and C10 (tertiary) vicinal stereocenters. The sterochemical outcome of the ?-ketoester alkylation appears to be governed by torsional steering in the transition state.

SUBMITTER: Moon NG

PROVIDER: S-EPMC5068569 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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A concise synthetic route to the stereotetrad core of the briarane diterpenoids.

Moon Nicholas G NG Harned Andrew M AM

Organic letters 20150414 9

A concise synthesis (under 10 steps) of the stereotetrad core of the briarane diterpenoids is reported. This approach harnesses the unique reactivity of salicylate ester derived 2,5-cyclohexadienones to quickly build complexity. In particular, a highly diastereoselective acetylide conjugate addition/β-ketoester alkylation sequence was used to set the relative configuration of the C1 (quaternary) and C10 (tertiary) vicinal stereocenters. The sterochemical outcome of the β-ketoester alkylation app ...[more]

PMID: 25871809

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