Ethionamide is a synthetic antimycobacterial active pharmaceutical ingredient (API) used in the treatment of tuberculosis. It is primarily used as part of combination therapy for patients with tuberculosis when other appropriate anti-tuberculosis medicines may not be suitable or effective.
Ethionamide belongs to the thioamide class of antimycobacterial agents and interferes with the synthesis of mycolic acids, important components of the Mycobacterium tuberculosis cell wall.
Ethionamide is a synthetic derivative of isonicotinic acid and contains a thioamide functional group. It is used primarily as a second-line antitubercular medicine in appropriate clinical settings.
CAS Number: 536-33-4
Molecular Formula: C₈H₁₀N₂S
Molecular Weight: 166.24 g/mol
Ethionamide is a prodrug that undergoes activation by mycobacterial enzymes, principally EthA. The activated metabolite interferes with enzymes involved in mycolic-acid biosynthesis, particularly InhA.
This results in:
Ethionamide is used in pharmaceutical formulations for:
Ethionamide is generally administered as part of a combination anti-tuberculosis regimen.
Ethionamide is a thioamide antimycobacterial API with defined chemical and physical characteristics. Pharmaceutical-grade material requires appropriate control of identity, assay, related substances and other quality attributes.
Typical quality evaluation may include:
Pharmaceutical-grade Ethionamide should comply with the applicable pharmacopoeial monograph, approved specification and regulatory requirements.
A qualified supplier should provide Certificate of Analysis (CoA), specification sheet, SDS/MSDS, batch traceability and applicable regulatory documentation.
Store Ethionamide in a tightly closed container, protected from excessive moisture, heat and direct light, according to the manufacturer's approved storage and stability requirements.
| Parameter | Specification |
|---|---|
| Appearance | White to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| Loss on Drying | NMT 1.0% |
| Residue on Ignition | NMT 0.5% |
| Heavy Metals | NMT 20 ppm |
| pH (1% Solution) | 2.0 – 4.0 |
| Individual Impurity | NMT 0.5% |
| Total Impurities | NMT 1.0% |