Methimazole
Description
Methimazole (CAS 60-56-0), also known by the trade name Tapazole and abbreviated as MMI, is an active pharmaceutical ingredient and synthesis intermediate used across pharmaceutical manufacturing and select industrial processes.
It functions as a thyroid hormone synthesis inhibitor in drug formulations and as a stabilizing agent in industrial chemical applications. In pharmaceutical manufacturing, MMI is the active substance in antithyroid drug products.
This makes it a direct procurement target for API suppliers and finished-dose formulators. Textile and leather processors source it as a corrosion inhibitor and stabilizing additive in processing baths where metal ion control is critical.
In paper manufacturing, it is applied as a biocide and preservation agent to extend the service life of process fluids. MMI also serves as a building block in heterocyclic synthesis for chemical production.
Its reactive thione group supports the production of more complex pharmaceutical intermediates. Methimazole is supplied as a white crystalline powder in bulk quantities suited to both pharmaceutical and industrial procurement.
Pharmaceutical-grade material is available to USP and BP specifications, supporting API and formulation manufacturing requirements. Technical-grade material is available for industrial applications.
Physical Properties
| Melting Point | 146-148 °C |
| Boiling Point | 280 °C |
| Density | 1.35 g/cm³ |
| Flash Point | 280°C |
| Appearance | White Solid |
| Color | White to slightly cream or pale buff |
| Form | Crystalline Powder |
| Water Solubility | soluble |
| Refractive Index | 1.5000 (estimate) |
Safety & Handling (Learn More)
Trade & Regulatory
| HS Code | 29332990 |
| Storage Class | 11 - Combustible Solids |
| WGK (Germany) | 3 |
Documentation
Other Names
1-methylimidazole-2(3H)-thione|1-methyl-1,3-dihydro-2H-imidazole-2-thione|Tapazole|1-Methyl-1H-imidazole-2-thiol|1-Methylimidazole-2-thiol|Mercazole|Thiamazol|2H-Imidazole-2-thione, 1,3-dihydro-1-methyl-|MMI
Related Products
Need a chemical? Get a quote within 24 hours.