A method of preparing a bis(thio-hydrazide amide) disalt includes the
steps of combining a neutral bis(thio-hydrazide amide), an organic
solvent and a base to form a bis(thio-hydrazide amide) solution; and
combining the solution and methyl tert-butyl ether, thereby precipitating
a disalt of the bis(thio-hydrazide amide).In some embodiments, a method
of preparing a bis(thio-hydrazide amide) disalt includes the steps of
combining a neutral bis(thio-hydrazide amide) and an organic solvent
selected from methanol, ethanol, acetone, and methyl ethyl ketone to make
a mixture; adding at least two equivalents of a base selected from sodium
hydroxide, potassium hydroxide, sodium methoxide, potassium methoxide,
sodium ethoxide and potassium ethoxide to the mixture, thereby forming a
solution; and combining the solution and methyl tert-butyl ether to
precipitate the disalt of the bis(thio-hydrazide amide).The disclosed
methods do not require lyophilization and the solvents used in the
process can be more readily removed to low levels consistent with
pharmaceutically acceptable preparation.