The present invention relates to tetrahydropyridine derivatives of formula (1) which may be therapeutically useful as anti-bacterial agents, more particularly FabI inhibitors.in which X, Y, Z and “n” have the same meanings given in the specification, and pharmaceutically acceptable salts and pharmaceutically acceptable stereoisomers thereof that are useful in the treatment and prevention in diseases or disorder, in particular their use in diseases or disorder where there is an advantage in inhibiting Enoyl-ACP reductase enzyme (FabI) activity.The present invention also provides methods for synthesizing and administering the FabI inhibitory compounds. The present invention also provides pharmaceutical formulations comprising at least one of the FabI inhibitory compounds together with a pharmaceutically acceptable carrier, diluent or excipient therefor.