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Updated: Jan 19, 2026

Spectrophotometric Screening for Potential Inhibitors of Cytosolic Glutathione S-Transferases
Published on: October 10, 2020
Nucleophilicity of Glutathione: A Link to Michael Acceptor Reactivities
Robert J Mayer1, Armin R Ofial1
1Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377, München, Germany.
Abstract:
Deprotonated glutathione is among the most potent biological nucleophiles and plays an important physiological role in cellular detoxification by forming covalent conjugates with Michael acceptors. The electrophilicity E of various Michael acceptors was characterized recently according to the Patz-Mayr relation lg k2 =sN (N+E). We now determined the nucleophilic reactivity (N, sN ) of glutathione (GSH) in aqueous solution at 20 °C to connect published GSH reactivities (kGSH ) with Mayr's electrophilicity scale (E). In this way, electrophilicities E of more than 70 Michael acceptors could be estimated, which can now be used to systematically predict novel reactions with the multitude of nucleophiles whose nucleophilicity parameters N/sN are known.
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