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The design and synthesis of alanine-rich ?-helical peptides constrained by an S,S-tetrazine photochemical trigger: a fragment union approach.

ABSTRACT: The design and synthesis of alanine-rich ?-helical peptides constrained in a partially unfolded state by incorporation of the S,S-tetrazine phototrigger has been achieved, permitting, upon photochemical release, observation by 2D-IR spectroscopy of the subnanosecond conformational dynamics that govern the early steps associated with ?-helix formation. Solid-phase peptide synthesis was employed to elaborate the requisite fragments, with full peptide construction via solution-phase fragment condensation. The fragment union tactic was also employed to construct (13)C?(18)O isotopically edited amides to permit direct observation of conformational motion at or near specific peptide bonds.

SUBMITTER: Courter JR

PROVIDER: S-EPMC3916828 | biostudies-other | 2014 Jan

REPOSITORIES: biostudies-other

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The design and synthesis of alanine-rich α-helical peptides constrained by an S,S-tetrazine photochemical trigger: a fragment union approach.

Courter Joel R JR Abdo Mohannad M Brown Stephen P SP Tucker Matthew J MJ Hochstrasser Robin M RM Smith Amos B AB

The Journal of organic chemistry 20131220 2

The design and synthesis of alanine-rich α-helical peptides constrained in a partially unfolded state by incorporation of the S,S-tetrazine phototrigger has been achieved, permitting, upon photochemical release, observation by 2D-IR spectroscopy of the subnanosecond conformational dynamics that govern the early steps associated with α-helix formation. Solid-phase peptide synthesis was employed to elaborate the requisite fragments, with full peptide construction via solution-phase fragment conden ...[more]

PMID: 24359446

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