Three tadalafil synthesis process byproducts and preparation method thereof

The invention discloses three tadalafil process byproducts, namely compounds shown as a formula I, a formula II and a formula III, and discloses a preparation method of the three impurities. The preparation method is simple, convenient to operate, mild and controllable in reaction condition and relatively high in product purity. The three can be used as reference substances for controlling the purity and quality of tadalafil raw material medicines and related preparations, is more beneficial to process research and quality control, and has higher application value. 本发明公开了三种他达拉非工艺副产物：式I、式II和式III化合物，并公开了该三种杂质的制备方法。制备方法简单，操作便捷，反应条件温和可控，产物纯度较高。三者可作为对照品用于控制他达拉非原料药及相关制剂的纯度和质量，更有利于工艺研究和质量控制，具有较高的应用价值。