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Concise total synthesis of (+/-)-salinosporamide A, (+/-)-cinnabaramide A, and derivatives via a bis-cyclization process: implications for a biosynthetic pathway?

ABSTRACT: 4-Alkylidene-beta-lactones (hetero ketene dimers) and alpha-amino acids are useful precursors for total syntheses of the beta-lactone-containing proteasome inhibitors salinosporamide A, cinnabaramide A, and derivatives. A key step is a nucleophile-promoted, bis-cyclization of keto acids that simultaneously generates the gamma-lactam and beta-lactone of these natural products. This reaction sequence may have implications for the biosynthesis of these natural products.

SUBMITTER: Ma G

PROVIDER: S-EPMC2518687 | biostudies-other | 2007 May

REPOSITORIES: biostudies-other

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Concise total synthesis of (+/-)-salinosporamide A, (+/-)-cinnabaramide A, and derivatives via a bis-cyclization process: implications for a biosynthetic pathway?

Ma Gil G Nguyen Henry H Romo Daniel D

Organic letters 20070504 11

4-Alkylidene-beta-lactones (hetero ketene dimers) and alpha-amino acids are useful precursors for total syntheses of the beta-lactone-containing proteasome inhibitors salinosporamide A, cinnabaramide A, and derivatives. A key step is a nucleophile-promoted, bis-cyclization of keto acids that simultaneously generates the gamma-lactam and beta-lactone of these natural products. This reaction sequence may have implications for the biosynthesis of these natural products. ...[more]

PMID: 17477539

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