Wy. Sun et al., ELECTROCHEMICAL MIMICKING OF REDUCED RUBREDOXIN BY IRON(II) COMPLEXESOF CYSTEINE PEPTIDE THIOLATE IN AQUEOUS MICELLE SOLUTION, Journal of electroanalytical chemistry [1992], 448(1), 1998, pp. 105-109
The electrochemical properties of Fe(II) complexes with a number of cy
steine-containing oligopeptides were investigated in aqueous Triton X-
100 (10%) micelle solution. The complexes with an aromatic ring such a
s [Fe(Z-cys-Pro-Leu-cys-Gly-NH-C6H4-p -F)(2)](2-), Z-cys-Pro-Leu-Cys-G
ly-NH-CH2-CH2-C6H4-p-F)(2)](2-) and [Fe(Z-cys-Pro-Leu-cys-Gly-Phe-OMe)
(2)](2-) exhibit their redox potentials at -0.28, -0.30 and -0.26 V vs
. SCE, respectively, in aqueous Triton X-100 (10%) micelle solution wi
th good reversibility. The potentials are very close to that of native
rubredoxin (-0.31 V vs. SCE in aqueous solution). A para-substituent
effect was observed for the redox potentials of [Fe(Z-cys-Pro-Leu-cys-
Gly-NH-C6H4-p-X)(2)](2-) (X = OMe, H, F and CN) in aqueous micelle sol
ution. The most positively shifted potential was found at -0.26 V vs.
SCE for the complex with the strongest electron-withdrawing cyano (CN)
substituent. The results show that the complexes with an aromatic rin
g are quite stable in such aqueous micelle solutions. (C) 1998 Elsevie
r Science S.A. All rights reserved.