In this paper the first synthesis of stable 3-hydroperoxy-sultams 3a-d
as well as the corresponding isothiazol-3(2H)-one I,l-dioxides 8a-e b
y oxidation of isothiazolium salts 6a-e is reported. The 3-hydroxy-sul
tams 7b-d are obtained by reduction of hydroperoxides 3b-d.