The invention provides a preparing method for tiagabine
hydrochloride, which includes the following operating steps: firstly, taking tiagabine
ethyl ester to be dissolved in
solvent, adding L-configuration
organic acid, performing heating
reflux until the tiagabine
ethyl ester is completely dissolved, then performing
reflux for 30-60 min, cooling to the
room temperature, cooling and crystallizing at the temperature of minus 30 -minus 20 DEG C, and collecting a
solid matter A; secondly, adding
solvent in the
solid matter A, performing heating
reflux until the tiagabine
ethyl ester is completely dissolved, then performing reflux for 30-60 min, cooling to the
room temperature, cooling and crystallizing at the temperature of minus 10-0 DEG C, and collecting a
solid matter B; thirdly, dissolving the
solid matter B, sequentially adding
sodium hydroxide and
hydrochloric acid to react, extracting and recrystallizing, so as to obtain the tiagabine
hydrochloride. The preparing method provided by the invention not only remarkably improves the productivity by 90% above, but also guarantees the 99.9% of chemical and optical purity, is simple and convenient to operate, has no special requirement for equipment, and is more suitable for large-scale industrial production.