Novel compounds belonging to the class of oxazolidinones possessing potent antimycobacterial properties especially useful in the treatment of acid fast organisms such as Mycobacterium tuberculosis, Mycobacterium avium-intracellular complex, M. fortuitum and M. kansai. The compound and its pharmaceutically acceptable salts act as antibacterial agents. Also mentioned is a method for inhibiting growth of mycobacterial cells as well as a method of treating mycobacterial conditions such as Mycobacterium tuberculosis, drug resistant Mycobacterium tuberculosis, Mycobacterium avium-intracellular complex, M. fortuitum and M. kansai., including administering an antimycobacterially effective amount of the compound and/or pharmaceutically acceptable salts. There is also mentioned a process for the manufacture of the compound or its pharmaceutically acceptable salts.