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Perthionitrite-Induced Persulfidation in Binuclear Cobalt(II) Complexes§
Anuj Baran Chakraborty1, Rajib Hazra1, Amit Majumdar1
1School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Kolkata700032, West Bengal, India.
Journal of the American Chemical Society
|July 14, 2026
Summary
This study shows that perthionitrite (SSNO⁻) can mediate the persulfidation of thiol groups, mimicking biological processes. This finding reveals a new role for SSNO⁻ in sulfur signaling pathways.
Area of Science:
- Bioinorganic Chemistry
- Sulfur Chemistry
- Biochemistry
Background:
- Persulfidation of thiols is a critical physiological process involving sulfur redox reactions.
- The exact mechanisms and mediating species in biological persulfidation remain incompletely understood.
Purpose of the Study:
- To investigate the role of dicobalt(II)-nitrito complexes in mediating persulfidation reactions.
- To explore the potential of perthionitrite (SSNO⁻) as a key species in thiol persulfidation.
Main Methods:
- Synthesis and characterization of dicobalt(II)-nitrito complexes and their reaction products.
- Utilized structural and spectroscopic methods for product and intermediate identification.
- Employed control experiments to validate reaction pathways.
Main Results:
- Two dicobalt(II)-nitrito complexes reacted with thiocarboxylic acids to yield persulfidated complexes in high yields.
- Identified perthionitrite (SSNO⁻) as a key intermediate generated in situ.
- Demonstrated that SSNO⁻ effectively persulfidates coordinated thiocarboxylates.
Conclusions:
- Perthionitrite (SSNO⁻) is shown to be an effective mediator for the persulfidation of sulfhydryl groups.
- This study provides the first evidence for SSNO⁻ mediating persulfidation, suggesting a potential biological role.
- Highlights a novel S/N-crosstalk mechanism relevant to physiological sulfur modifications.
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