Ongoing work in our group is aimed at identifying and characterizing unique metal-ligand interactions that can be used to constrain peptides to specific secondary structures.  One system that has been under active exploration is tungsten-alkyne coordination, since the tungsten can coordinate two alkyne ligands to produce an air-stable species.  Alkynes are not found in the structures of the 20 common amino acids, so we have investigated the ability of synthetic, alkynylamino acids to coordinate to tungsten.  In this presentation, the synthesis and coordination of peptides bearing two of these alkynylamino acids will be detailed.  The resulting complexes are cyclic species that incorporate the tungsten in the ring - metallacyclicpeptides.  In addition, the conformational analysis of these metallacyclicpeptides will be detailed.  Finally, the ability of a pentapeptide bearing two propargylcysteines to form a metallacycle and to adopt an a-helical conformation will be presented.

Constrained peptides constructed by coordination of propargylcysteines with tungsten

242nd National Meeting (2011)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.