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Title: Lewis Acid Coordination Redirects S‐Nitrosothiol Signaling Output
Abstract

S‐Nitrosothiols (RSNOs) serve as air‐stable reservoirs for nitric oxide in biology. While copper enzymes promote NO release from RSNOs by serving as Lewis acids for intramolecular electron‐transfer, redox‐innocent Lewis acids separate these two functions to reveal the effect of coordination on structure and reactivity. The synthetic Lewis acid B(C6F5)3coordinates to the RSNO oxygen atom, leading to profound changes in the RSNO electronic structure and reactivity. Although RSNOs possess relatively negative reduction potentials, B(C6F5)3coordination increases their reduction potential by over 1 V into the physiologically accessible +0.1 V vs. NHE. Outer‐sphere chemical reduction gives the Lewis acid stabilized hyponitrite dianiontrans‐[LA‐O‐N=N‐O‐LA]2−[LA=B(C6F5)3], which releases N2O upon acidification. Mechanistic and computational studies support initial reduction to the [RSNO‐B(C6F5)3] radical anion, which is susceptible to N−N coupling prior to loss of RSSR.

 
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NSF-PAR ID:
10145076
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie
Volume:
132
Issue:
27
ISSN:
0044-8249
Page Range / eLocation ID:
p. 10946-10950
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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