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Evaluation of a cyclopentane-based ?-amino acid for the ability to promote ?/?-peptide secondary structure.

ABSTRACT: We report the asymmetric synthesis of the ?-amino acid (1R,2R)-2-aminomethyl-1-cyclopentane carboxylic acid (AMCP) and an evaluation of this residue's potential to promote secondary structure in ?/?-peptides. Simulated annealing calculations using NMR-derived distance restraints obtained for ?/?-peptides in chloroform reveal that AMCP-containing oligomers are conformationally flexible. However, additional evidence suggests that an internally hydrogen-bonded helical conformation is partially populated in solution. From these data, we propose characteristic NOE patterns for the formation of the ?/?-peptide 12/10-helix and discuss the apparent conformational frustration of AMCP-containing oligomers.

SUBMITTER: Giuliano MW

PROVIDER: S-EPMC4109159 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature

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Evaluation of a cyclopentane-based γ-amino acid for the ability to promote α/γ-peptide secondary structure.

Giuliano Michael W MW Maynard Stacy J SJ Almeida Aaron M AM Reidenbach Andrew G AG Guo Li L Ulrich Emily C EC Guzei Ilia A IA Gellman Samuel H SH

The Journal of organic chemistry 20131205 24

We report the asymmetric synthesis of the γ-amino acid (1R,2R)-2-aminomethyl-1-cyclopentane carboxylic acid (AMCP) and an evaluation of this residue's potential to promote secondary structure in α/γ-peptides. Simulated annealing calculations using NMR-derived distance restraints obtained for α/γ-peptides in chloroform reveal that AMCP-containing oligomers are conformationally flexible. However, additional evidence suggests that an internally hydrogen-bonded helical conformation is partially popu ...[more]

PMID: 24303945

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Dataset Information

Evaluation of a cyclopentane-based ?-amino acid for the ability to promote ?/?-peptide secondary structure.

Publications

Evaluation of a cyclopentane-based γ-amino acid for the ability to promote α/γ-peptide secondary structure.

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