(6,7-Dihydro-2-nitro-5H-imidazo [2,1-b][1,3]oxazin-6-yl)amide compounds of formula (I), and their pharmaceutically acceptable salts, preparation methods and pharmaceutical compositions thereof are disclosed, wherein m and R are defined as in the description. The uses of said compounds in preparing medicaments for treating infectious diseases caused by Mycobacterium tuberculosis, especially infectious diseases caused by multi-drug resistance Mycobacterium tuberculosi are also disclosed.
