The invention discloses a preparation method of
tiamulin and
tiamulin fumarate based on
Bunte salt, which comprises the following steps: mixing the
Bunte salt and
pleuromutilin p-toluenesulfonate, reacting at 45-65 DEG C for 3-5 hours to synthesize
tiamulin, preparing the
Bunte salt through a reaction formula 1, and preparing the
pleuromutilin p-toluenesulfonate through a reaction formula 2, the
molar ratio of the 2-diethylaminoethanol to the
sodium thiosulfate to the chlorination
reagent in the reaction formula 1 is 1: (1-1.3): (1-1.5), and the
molar ratio of the
pleuromutilin to the paratoluensulfonyl
chloride to the
pyridine in the reaction formula 2 is 1: (1-1.2): (1-1.2); the prepared tiamulin and
fumaric acid are used as raw materials for a salt forming reaction, the
reaction temperature ranges from 55 DEG C to 65 DEG C, the reaction time ranges from 40 min to 80 min, and after the reaction is finished, the tiamulin fumarate is prepared through cooling,
crystallization,
centrifugation and
drying; the tiamulin fumarate disclosed by the invention is high in content, low in total amount of impurities, few in variety and stable in quality under high-temperature and high-
humidity conditions, and the preparation method is simple and easy to operate and good in product quality.