The invention relates to Form I of N-n-propyl-3-(4-methylphenyl)-4-(4-methylsulfonylphenyl)-2,5-dihydropyrr ole-2-one and preparation method thereof. The method includes that solid arbitrary or amorphous form of N-n-propyl-3-(4-methylphenyl)-4-(4-methylsulfonylphenyl)-2,5-dihydropyrrole-2-one was crystallized with polar organic solvents or their aqueous solution to obtain Form I of N-n-propyl-3-(4-methylphenyl)-4-(4-methylsulfonylphenyl)-2,5-dihydropyrrole-2-one. The received Form I, which can be better used for clinical treatment,has a good crystal stability and chemical stability, and solvent used for crystallization has low toxicity and residue.本發明涉及N-正丙基-3-(4-甲基苯基)-4-(4-甲磺醯基苯基)-2,5-二氫吡咯-2-酮I型結晶及其製備方法。該方法包括將任意晶型或非晶型的N-正丙基-3-(4-甲基苯基)-4-(4-甲磺醯基苯基)-2,5-二氫吡咯-2-酮固體,使用極性有機溶劑或者它們的水溶液予以結晶,得到N-正丙基-3-(4-甲基苯基)-4-(4-甲磺醯基苯基)-2,5-二氫吡咯-2-酮I型結晶。本發明所得到的N-正丙基-3-(4-甲基苯基)-4-(4-甲磺醯基苯基)-2,5-二氫吡咯-2-酮I型結晶具備良好的晶型穩定性和化學穩定性,並且所使用之結晶溶劑為低毒性、低殘留,可更好地用於臨床治療。由於本案的圖為試驗化合物的圖譜,並非本案的代表圖。故本案無指定代表圖。
