Abstract
Water-soluble MoO2(cys-O-PEG)2 as a model for molybdo-oxidases was prepared from t-butyloxycarbonyl-L-cysteine(S-acetamidomethyl)-O-(CH2CH2O)n–OH (t-Boc-Cys(Acm)-O-PEG, n=45), and HgCl (t-Boc-cys-O-PEG). The macromolecular Mo(VI) complex readily decomposed in water, forming a disulfide derived from the cys-PEG ligands. MoO2(cys-O-PEG)2 in water causes the catalytic air oxidation of PPh3 or P(OMe)3. The role of the hydrophobic environment surrounding the active site of molybdenum oxidase was found to protect the Mo(VI)/ Mo(V) site from water in bulk. The model dioxo-Mo(VI) complexes are generally insoluble in water thus making it impossible to examine their redox behavior toward biological redox agents.
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Ueyama, N., Kamada, E. & Nakamura, A. Cysteine-Thiolato Dioxomolybdenum(VI) Species Supported by Water Soluble Poly(ethylene glycol) as a Molybdo-Oxidase Model. Its Enhanced Oxidative Ability in Water as Shown by the CD Spectral Investigation. Polym J 15, 519–524 (1983). https://doi.org/10.1295/polymj.15.519
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DOI: https://doi.org/10.1295/polymj.15.519