Terizidone API is a synthetic cyclic derivative and prodrug of D-cycloserine used as an anti-tuberculosis pharmaceutical ingredient. It is primarily associated with treatment regimens for drug-resistant tuberculosis, including multidrug-resistant tuberculosis (MDR-TB). Terizidone is converted in the body to cycloserine-related active species and contributes to inhibition of mycobacterial cell-wall synthesis.
Terizidone has the molecular formula C₁₄H₁₄N₄O₄, CAS 25683-71-0, and molecular weight approximately 302.29 g/mol. Its chemical structure contains two oxazolidinone-derived units connected through a substituted phenylene methylene-imine system.
WHO documentation for a prequalified Terizidone product identifies Terizidone as a prodrug and describes control of its stereochemical composition, related substances, assay, residual solvents and polymorphic form.
Terizidone is a stereochemically defined compound. The R,R configuration associated with the D-cycloserine-derived structure is retained during its synthesis, while other stereoisomeric forms are controlled as impurities. WHO's assessment also notes that Terizidone exhibits polymorphism and that control of the relevant polymorphic form is part of API quality evaluation.
Terizidone is structurally related to cycloserine and functions as a prodrug. It undergoes biological conversion to cycloserine-related active material, which interferes with enzymes involved in peptidoglycan synthesis and consequently affects mycobacterial cell-wall formation.
Terizidone is used as an anti-tuberculosis pharmaceutical ingredient, particularly in treatment regimens for drug-resistant tuberculosis.
WHO prequalification documentation includes Terizidone 250 mg capsules and describes its quality and stability requirements. Terizidone is also included among the medicines covered by WHO's tuberculosis-related prequalification activities.
Because tuberculosis treatment requires combination therapy, Terizidone is used as part of an appropriate multidrug regimen rather than as a standalone treatment.
Terizidone acts as a prodrug of D-cycloserine. Following conversion to active cycloserine-related material, it interferes with enzymes involved in bacterial cell-wall synthesis.
The resulting inhibition of peptidoglycan biosynthesis affects the ability of Mycobacterium tuberculosis to maintain its cell wall, contributing to the antimycobacterial activity of the treatment regimen.
Terizidone requires analytical controls appropriate for a stereochemically defined and polymorphic pharmaceutical API.
WHO's API assessment specifically identifies testing for:
WHO specifies control of the combined Terizidone diastereomer and enantiomer content at NMT 0.2% in the referenced API specification.
Swapnroop Drugs and Pharmaceuticals focuses on quality-oriented pharmaceutical API manufacturing for pharmaceutical development and manufacturing requirements.
For Terizidone, important quality attributes include chemical identity, assay, chromatographic purity, stereochemical purity, water content, residual solvents, polymorphic form and control of synthesis-related impurities.
Terizidone API should be packed in suitable pharmaceutical-grade, well-closed packaging that protects the material from moisture, contamination and unsuitable environmental exposure.
Storage conditions should follow validated stability data and the applicable product/API specification. WHO documentation reports stability evaluation under long-term and accelerated conditions and notes the importance of controlling moisture and degradation during storage.
Depending on customer and regulatory requirements, documentation may include:
Swapnroop Drugs and Pharmaceuticals focuses on quality-oriented pharmaceutical API manufacturing and analytical control.
For Terizidone, emphasis is placed on identity, assay, related substances, stereochemical purity, water content, residual solvents, particle characteristics and polymorphic control in accordance with the applicable pharmaceutical specification.
Swapnroop Drugs and Pharmaceuticals — quality-focused pharmaceutical API manufacturing from India.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |