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Abstract Hydrogen sulfide (H2S) and nitric oxide (NO) are important gaseous biological signaling molecules that are involved in complex cellular pathways. A number of physiological processes require both H2S and NO, which has led to the proposal that different H2S/NO⋅ crosstalk species, including thionitrite (SNO−) and perthionitrite (SSNO−), are responsible for this observed codependence. Despite the importance of these S/N hybrid species, the reported properties and characterization, as well as the fundamental pathways of formation and subsequent reactivity, remain poorly understood. Herein we report new experimental insights into the fundamental reaction chemistry of pathways to form SNO−and SSNO−, including mechanisms for proton‐mediated interconversion. In addition, we demonstrate new modes of reactivity with other sulfur‐containing potential crosstalk species, including carbonyl sulfide (COS).
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Thionitrite (SNO − ) and Perthionitrite (SSNO − ) are Simple Synthons for Nitrosylated Iron Sulfur Clusters
Abstract S/N crosstalk species derived from the interconnected reactivity of H2S and NO facilitate the transport of reactive sulfur and nitrogen species in signaling, transport, and regulatory processes. We report here that simple Fe2+ions, such as those that are bioavailable in the labile iron pool (LIP), react with thionitrite (SNO−) and perthionitrite (SSNO−) to yield the dinitrosyl iron complex [Fe(NO)2(S5)]−. In the reaction of FeCl2with SNO−we were able to isolate the unstable intermediate hydrosulfido mononitrosyl iron complex [FeCl2(NO)(SH)]−, which was characterized by X‐ray crystallography. We also show that [Fe(NO)2(S5)]−is a simple synthon for nitrosylated Fe−S clusters via its reduction with PPh3to yield Roussin's Red Salt ([Fe2S2(NO)4]2−), which highlights the role of S/N crosstalk species in the assembly of fundamental Fe−S motifs.
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- Award ID(s):
- 2107602
- PAR ID:
- 10445784
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 61
- Issue:
- 30
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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