A process for preparing a compound of formula (I):
or a pharmaceutically acceptable salt thereof includes reacting a compound of formula (6):
(wherein R is H) with 2-aminocyclohexanol or a salt thereof.
                            一种制备式(I)化合物的工艺:
或其药学上可接受的盐的工艺,包括使式(6)化合物反应:
(其中 R 为 H)与 
2-氨基环己醇或其盐。