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Nucleophilicity of Glutathione: A Link to Michael Acceptor Reactivities.

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 =s_N (N+E). We now determined the nucleophilic reactivity (N, s_N ) of glutathione (GSH) in aqueous solution at 20?°C to connect published GSH reactivities (k_GSH ) 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/s_N are known.

SUBMITTER: Mayer RJ

PROVIDER: S-EPMC6899611 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Nucleophilicity of Glutathione: A Link to Michael Acceptor Reactivities.

Mayer Robert J RJ Ofial Armin R AR

Angewandte Chemie (International ed. in English) 20191031 49

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 reactiv ...[more]

PMID: 31560405

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