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Chemical trapping and characterization of small oxoacids of sulfur (SOS) generated in aqueous oxidations of H₂S.

ABSTRACT: Small oxoacids of sulfur (SOS) are elusive molecules like sulfenic acid, HSOH, and sulfinic acid, HS(O)OH, generated during the oxidation of hydrogen sulfide, H₂S, in aqueous solution. Unlike their alkyl homologs, there is a little data on their generation and speciation during H₂S oxidation. These SOS may exhibit both nucleophilic and electrophilic reactivity, which we attribute to interconversion between S(II) and S(IV) tautomers. We find that SOS may be trapped in situ by derivatization with nucleophilic and electrophilic trapping agents and then characterized by high resolution LC MS. In this report, we compare SOS formation from H₂S oxidation by a variety of biologically relevant oxidants. These SOS appear relatively long lived in aqueous solution, and thus may be involved in the observed physiological effects of H₂S.

SUBMITTER: Kumar MR

PROVIDER: S-EPMC5680521 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Chemical trapping and characterization of small oxoacids of sulfur (SOS) generated in aqueous oxidations of H2S.

Kumar Murugaeson R MR Farmer Patrick J PJ

Redox biology 20171016

Small oxoacids of sulfur (SOS) are elusive molecules like sulfenic acid, HSOH, and sulfinic acid, HS(O)OH, generated during the oxidation of hydrogen sulfide, H2S, in aqueous solution. Unlike their alkyl homologs, there is a little data on their generation and speciation during H2S oxidation. These SOS may exhibit both nucleophilic and electrophilic reactivity, which we attribute to interconversion between S(II) and S(IV) tautomers. We find that SOS may be trapped in situ b ...[more]

PMID: 29096321

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