Synthesis, crystal structures, electrochemical and protein-binding properties of ferrocene-indole conjugates

This paper describes the synthesis, characterisation and electrochemical properties of three redox-active ferrocene-indole compounds, N-(ferrocenylmethylenyl)tryptamine (Fc-CH=NC₂H₄-indole) (Fc1), N-(ferrocenylmethyl)tryptamine (Fc-CH₂NHC₂H ₄-indole) (Fc2) and indole-3-(N-(6-(N-ferrocenylmethyl)aminohexyl)) carboxamide (Fc-CH₂NHC₆H₁₂NHCO-indole) (Fc3). The X-ray crystal structures of Fc1 and Fc2 have been investigated. The recognition of the redox-active ferrocene-indole compounds Fc2 and Fc3 by indole-binding proteins including bovine serum albumin and tryptophanase has been studied by electrochemical and luminescence titrations and enzyme inhibition assays. © the Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2006.