The invention discloses a refining method of
fasudil hydrochloride. The method comprises the following steps: reacting homopiperazine with 5-
isoquinoline sulfonyl chloride to obtain
Fasudil free alkali, dissolving the
Fasudil free alkali in a
solvent A, uniformly mixing, dropwise adding
hydrochloric acid into the solution at a constant temperature to adjust the pH value, stirring the solution at alow temperature to crystallize, filtering,
drying a
filter cake to constant weight to obtain
Fasudil dihydrochloride, dissolving
fasudil dihydrochloride in a
solvent B, mixing, adding
sodium hydroxide to adjust the pH value, separating the liquid, filtering the organic phase to obtain a filtrate, adding
hydrochloric acid into the filtrate at constant temperature, stirring to crystallize, filtering, and
drying the
filter cake to obtain the
fasudil hydrochloride refined product. According to the method, impurities in the fasudil
hydrochloride can be effectively removed, the total
impurity content is controlled to be 0.1% or below, the single
impurity content is controlled to be 0.05% or below, the content is 99% or above, the pH value of the fasudil hydrochloride is effectively controlled to be 4.5-6.0, traditional
column chromatography operation is avoided, and industrial production is facilitated.