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Structural characterization of an enantiomerically pure amino acid imidazolide and direct formation of the beta-lactam nucleus from an alpha-amino acid.

ABSTRACT: Decomposition of a diazo beta-ketoamide derived from N-trityl serine imidazolide and N-protected acetanilides provides, instead of the expected 3-acyloxindole product, an enantiomerically pure (EP) beta-lactam. The amino acid stereocenter is incorporated, the second chiral center is induced, and trityl protection of the beta-lactam ring is realized for the first time. The desired 3-acyloxindole is obtained from oxindole and Tr-Ser(OBn)-imidazole, the X-ray of which provides the first structural determination of an EP amino acid imidazolide.

SUBMITTER: Gerstenberger BS

PROVIDER: S-EPMC2597468 | biostudies-literature | 2008 Feb

REPOSITORIES: biostudies-literature

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Structural characterization of an enantiomerically pure amino acid imidazolide and direct formation of the beta-lactam nucleus from an alpha-amino acid.

Gerstenberger Brian S BS Lin Jinzhen J Mimieux Yvette S YS Brown Lauren E LE Oliver Allen G AG Konopelski Joseph P JP

Organic letters 20080109 3

Decomposition of a diazo beta-ketoamide derived from N-trityl serine imidazolide and N-protected acetanilides provides, instead of the expected 3-acyloxindole product, an enantiomerically pure (EP) beta-lactam. The amino acid stereocenter is incorporated, the second chiral center is induced, and trityl protection of the beta-lactam ring is realized for the first time. The desired 3-acyloxindole is obtained from oxindole and Tr-Ser(OBn)-imidazole, the X-ray of which provides the first structural ...[more]

PMID: 18181633

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