Disclosed are a process for the preparation of a compound represented by the formula (1), which comprises treating a compound represented by the formula (2) with methanesulfonic acid and then subjecting the thus-treated compound to recrystallization; and Compound (1) so obtained.
This Compound (1) is free of hygroscopicity, excellent in filterability and solubility and easy in handling. Furthermore, according to the preparation process of the present invention, an unnecessary isomer can be converted into the target one and separation of the target isomer can be conducted easily.
本发明公开了一种制备式 (1) 所代表化合物的工艺,该工艺包括用
甲磺酸处理式 (2) 所代表的化合物,然后将经如此处理的化合物进行重结晶;以及如此获得的化合物 (1)。
这种化合物(1)无吸湿性,过滤性和溶解性极佳,易于处理。此外,根据本发明的制备工艺,不必要的异构体可转化为目标异构体,目标异构体的分离也很容易进行。