The present invention provides a key new intermediate (a compound of formula III) of 4-benzyl-1-phenethyl-piperazine-2,6-dione (formula IV compound), a pharmaceutically acceptable salt thereof and a preparation method thereof. The present invention additionally discloses a method for preparing 4-benzyl-1-phenethyl-piperazine-2,6-dione (formula IV compound) from the formula III compound, said method overcoming the shortcomings of current formula IV compound preparation methods, such as low production volumes, low purity, high energy consumption, high costs, and inability to achieve industrialized production, and provides a formula IV compound preparation method which is simple, economical, environmentally-friendly and easy to produce industrially; the reaction solvent of the method is easily recycled and the method can produce the formula IV compound at high production rates and with high purity.
本发明提供了4-苄基-
1-苯乙基哌嗪-2,6-二酮(公式IV化合物)的一个关键新中间体(公式III化合物),其在药学上可接受的盐和制备方法。本发明还公开了一种从公式III化合物制备4-苄基-
1-苯乙基哌嗪-2,6-二酮(公式IV化合物)的方法,该方法克服了当前公式IV化合物制备方法的缺点,如生产量低、纯度低、能量消耗高、成本高和无法实现工业化生产,并提供了一种简单、经济、环保且易于工业化生产的公式IV化合物制备方法;该方法的反应溶剂易于回收,能够高产高纯度地生产公式IV化合物。