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Stereospecific synthesis of conformationally constrained gamma-amino acids: new foldamer building blocks that support helical secondary structure.

ABSTRACT: A highly stereoselective synthesis of novel cyclically constrained gamma-amino acid residues is presented. The key step involves organocatalytic Michael addition of an aldehyde to 1-nitrocyclohexene. After aldehyde reduction, this approach provides optically active beta-substituted delta-nitro alcohols (96-99% ee), which can be converted to gamma-amino acid residues with a variety of substituents at the alpha position. We have used these new building blocks to prepare alpha/gamma-peptide foldamers that adopt a specific helical conformation in solution and in the solid state.

SUBMITTER: Guo L

PROVIDER: S-EPMC2843141 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature

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Stereospecific synthesis of conformationally constrained gamma-amino acids: new foldamer building blocks that support helical secondary structure.

Guo Li L Chi Yonggui Y Almeida Aaron M AM Guzei Ilia A IA Parker Brian K BK Gellman Samuel H SH

Journal of the American Chemical Society 20091101 44

A highly stereoselective synthesis of novel cyclically constrained gamma-amino acid residues is presented. The key step involves organocatalytic Michael addition of an aldehyde to 1-nitrocyclohexene. After aldehyde reduction, this approach provides optically active beta-substituted delta-nitro alcohols (96-99% ee), which can be converted to gamma-amino acid residues with a variety of substituents at the alpha position. We have used these new building blocks to prepare alpha/gamma-peptide foldame ...[more]

PMID: 19886693

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