The present invention discloses antitubercular compounds selected from tetrahydropyrimidones/ tetrahydrothiopyrimidone derivatives of Formula 1 and its pharmaceutically acceptable salts for the treatment of Mycobacterium in the dormant phase. wherein, R is H, halogen, dihalogen, O-alkyl, di- O-alkyl , R1 is phenyl, chlorophenyl, nitrophenyl, diclorophenyl, cycloalkyl preferably cyclohexyl, X is O or S.