 Nitration gives nitrodisulfonic acids, which are precursors to amino derivatives.The disodium salt is sometimes used as a divalent counterion for forming salts of basic drug compounds, as an alternative to the related mesylate or tosylate salts.When used in this way such a salt is called a naphthalenedisulfonate salt, as seen with the most common salt form of the stimulant drug CFT.