Metal Coordination to Unsymmetric 1, n′‐Disubstituted Ferrocene Histidine Peptides. Issue 27 (10th July 2018)

• Record Type: Journal Article
• Authors: Ferranco, Annaleizle; Sun, Keija; Udaipaul, Theodore; Kraatz, Heinz‐Bernhard
• Is Part Of: European journal of inorganic chemistry. Issue 27(2018)
• Page Start: 3213
• Page End: 3223
• Publication Date: 2018-07-10
• Subjects: Peptides -- Coordination modes -- Iron -- Bioorganometallic chemistry; Chemistry, Inorganic -- Periodicals; Organometallic chemistry -- Periodicals; Bioinorganic chemistry -- Periodicals; Solid state chemistry -- Periodicals; 546
• DOI: 10.1002/ejic.201800455
• Languages: English
• ISSNs: 1434-1948

Abstract

Abstract : In this study, the coordination chemistry of unsymmetrical 1, n ′‐substituted ferrocene (Fc) peptide conjugates is explored, where the peptide substituents are two different histidine‐containing peptides. The resulting Fc‐conjugates serve as ligands for the formation of metal complexes, with the intention to generate complexes that possess a labile coordination site. The following Fc[CO‐His(Trt)‐OMe][COOMe] (1 ), Fc[CO‐His(Trt)‐Gly‐OMe][CO‐Gly‐OMe] (2 ), Fc[CO‐His(Trt)‐His(Trt)‐OMe][CO‐His(Trt)‐OMe] (3 ), and Fc[CO‐His(Trt)‐Gly‐His(Trt)‐OMe][CO‐Gly‐His(Trt)‐OMe] (4 ) were synthesized and characterized. Each compound forms discrete complexes with metal divalent metal ions Zn 2+, Co 2+ and Cd 2+, where a single metal ion is complexed by the metallo‐ligand, as was confirmed spectroscopically. The redox properties of the Fc group are influenced by metal coordination to the peptide substituents and anodic shifts occur upon the addition of metal ions. These follow the order Zn 2+ > Cd 2+ > Co 2+ . NMR experiments indicated imidazole rings are the site of metal coordination. Fc‐peptide conjugates display a switchable axial chirality that is dependent on metal complexation. Abstract : Ferrocene‐histidine derivatives serve as metallo‐ligands that can coordinate the Zn 2+ ion, forming complexes with a labile coordination site.