Other Names: Isonicotinic acid hydrazide, Isoniazidazine, Isozid
Molecular Formula: C6H7N3O
Molecular Weight: 137.14
CAS Number: 54-85-3
Pharmacological Actions
Isoniazid is an extremely effective antituberculosis drug, primarily working by inhibiting the synthesis of the cell wall of Mycobacterium tuberculosis. The specific mechanisms are as follows:
Inhibition of Cell Wall Synthesis: Isoniazid inhibits the synthesis of acyl carrier protein (ACP) and dehydratase, which are required for the synthesis of the bacterial cell wall in Mycobacterium tuberculosis, thereby blocking cell wall synthesis.
Activation into Active Form: Isoniazid needs to be metabolized into its active form by the catalase-peroxidase enzyme (KatG) encoded by the katG gene of Mycobacterium tuberculosis to exert its antibacterial effect.
Bactericidal Action: Isoniazid has a strong bactericidal effect on rapidly multiplying Mycobacterium tuberculosis; it is less effective against slowly growing mycobacteria.
