<unk>  is the disulfonyl derivative of the neuroprotective nitrone spin trap phenylbutylnitrone or "PBN". PBN and its derivatives hydrolyze and oxidize in vitro to form respectively MNP-OH (AKA, NtBHA) and its parent spin-trap MNP.
Disufenton sodium
Fomepizole
Fermagate
Sodium thiosulfate 
Methylene blue
Dimercaprol
Malaoxon
Dianethole