A process for obtaining therapeutically active 2-[4-(3- and 2-(fluorobenzyloxy)benzylamino]propanamides, and their salts with pharmaceutically acceptable acids with high purity degree, in particular, with a content of dibenzyl derivatives impurities lower than 0.03%, preferably lower than 0.01% by weight. The process is carried out by submitting the Schiff bases intermediates 2-[4-(3- and 2-fluorobenzyloxy)benzylideneamino]propanamides to a reduction reaction with a reducing agent selected from sodium borohydride and potassium borohydride in an appropriate amount of an organic solvent selected from C
1
-C
5
lower alkanols, allowing the formation and presence during a substantial position of the reduction reaction course of a suspension of the Schiff base into the saturated solution of the Schiff base into the same organic solvent.
一种制备具有高纯度的治疗活性2-[4-(3-和2-(
氟苯甲氧基)苯基)
氨基]丙酰胺及其盐的方法,其杂质二苯甲基衍
生物含量低于0.03%,优选低于0.01%。该方法通过将席夫碱中间体2-[4-(3-和2-
氟苯甲氧基)苯基
亚胺基]丙酰胺与选择自C1-C5低级醇的有机溶剂的适当量还原剂(如氢
硼酸钠和氢
硼酸钾)进行还原反应,使得在还原反应过程中席夫碱的悬浮液形成并存在于同一有机溶剂的饱和溶液中。