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Synthesis of the cores of hypocrellin and shiraiachrome: diastereoselective 1,8-diketone aldol cyclization.

ABSTRACT: Intramolecular 1,8-diketone aldol reactions were studied as a tool for the construction of the seven-membered rings of hypocrellin and shiraiachrome. Conditions were identified to obtain the relative stereochemistries present in the two natural products with excellent diastereoselectivity. In addition, a nine-membered ring congener, which has yet to be observed in nature, formed with high selectivity when a hindered amine was used in conjunction with silazide bases.

SUBMITTER: O'Brien EM

PROVIDER: S-EPMC2798919 | biostudies-literature | 2010 Jan

REPOSITORIES: biostudies-literature

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Synthesis of the cores of hypocrellin and shiraiachrome: diastereoselective 1,8-diketone aldol cyclization.

O'Brien Erin M EM Li Jingxian J Carroll Patrick J PJ Kozlowski Marisa C MC

The Journal of organic chemistry 20100101 1

Intramolecular 1,8-diketone aldol reactions were studied as a tool for the construction of the seven-membered rings of hypocrellin and shiraiachrome. Conditions were identified to obtain the relative stereochemistries present in the two natural products with excellent diastereoselectivity. In addition, a nine-membered ring congener, which has yet to be observed in nature, formed with high selectivity when a hindered amine was used in conjunction with silazide bases. ...[more]

PMID: 19894740

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