Synthesis and Structural Stability of α-Helical Gold(I)-Metallopeptidesy

Published as part of the series Thieme Chemistry Journals Awardees – Where Are They Now?

Abstract

The synthesis of hexa- and dodecapeptides functionalized with two Au(I)–phosphine complexes is reported. The high stability of the Au(I)–phosphine bond allowed orthogonal peptide-protecting-group chemistry, even when using hard Lewis acids like boron tribromide. This enabled the preparation of an Fmoc-protected lysine derivative carrying the Au(I) complex in a side chain, which was used in standard Fmoc-based solid-phase peptide synthesis protocols. Alanine and leucine repeats in the metallododecapeptide formed α-helical secondary structures in 2,2,2-trifluoroethanol–H₂O and 1,1,1,3,3,3-hexafluoroisopropanol–H₂O mixtures with high thermal stability, as shown by temperature-dependent CD spectroscopy studies.

Key words

metallopeptides - gold complexes - peptide folding - α-helix - supramolecular chemistry - circular dichroism

Publication History

Received: 16 August 2020

Accepted after revision: 15 October 2020

Accepted Manuscript online:
15 October 2020

Article published online:
20 November 2020

• References and Notes

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