The invention relates to a preparation method of high-purity
dexrazoxane, which comprises the following steps of: (1) cyclization reaction: carrying out cyclization reaction between (S)-1, 2-
propane diamine-N, N, N', N'-tetracetic acid or disodium salt of (S)-1, 2-
propane diamine-N, N, N', N'-tetracetic acid and
formamide, wherein a high
boiling point solvent is used; (2) preparation of salt-containing crude product: evaporating the mixture, which is obtained after reaction, for removing the
formamide by
pressure reduction and concentration, adding
organic solvent into the mixture, and filtering to obtain
solid; (3) preparation of crude product: adding dioxane into the salt-containing crude product, heating for
backflow, filtering, concentrating the filtrate, adding
organic solvent into the filtrate to obtain the crude product of
dexrazoxane; and (4) refining: adding the crude product of
dexrazoxane into N, N'-
dimethyl formamide, heating for dissolving, dropwise adding the
solvent, carrying out
crystallization, filtering to obtain
solid, washing the obtained
solid with the
solvent,
drying to finally obtain the high-purity dexrazoxane. The method for synthesizing dexrazoxane is stable in yield and easy in condition control; the product purity is higher than 99.5% and residual
organic solvent is little, and the synthesis cost can be reduced.