Reactions of NO and NO2 with Thiols

Although the biological relevance of these processes has yet to be established, it has been reported that NO is capable of oxidizing sulfhydryl groups under basic conditions. The net products of this reaction are the corresponding disulfide and hyponitrous acid [reactions (12)-(14)] (Pryor etal, 1982). 

Also of chemical interest (but of unestablished physiological relevance) is the reported reduction of NO2 to NO by sulfhydryl groups through the presumed intermediacy of a nitrosothiol [reactions (15)-(17)] (Pryor et al, 1982). 

NO can be derived from this reaction since the S—NO bond is relatively weak [reaction (17)]. 

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