Energetics of an n --> pi interaction that impacts protein structure.
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ABSTRACT:
SUBMITTER: Hodges JA
PROVIDER: S-EPMC2625295 | biostudies-literature | 2006 Oct
REPOSITORIES: biostudies-literature
Publications
Energetics of an n --> pi interaction that impacts protein structure.
Hodges Jonathan A JA Raines Ronald T RT
Organic letters 20061001 21
[structure: see text] The trans/cis ratio of the amide bond in N-formylproline phenylesters correlates with electron withdrawal by a para substituent. The slope of the Hammett plot (rho = 0.26) is indicative of a substantial effect. This effect arises from a favorable n --> pi interaction between the amide oxygen and ester carbonyl. In a polypeptide chain, an analogous interaction can stabilize the conformation of trans peptide bonds, alpha-helices, and polyproline type-II helices. ...[more]
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