Carbimazole
CAS: 22232-54-8
Category: Pharmaceutical Intermediates
| Purity | Reagent Grade ≥98%, Pharmaceutical Grade ≥99%, Reference Standard ≥99.5% |
| Molecular Formula | C7H10N2O2S |
| Molecular Weight | 186.23 |
| Appearance | White to off-white crystalline powder |
| Packaging | 1 g/glass vial, 5 g/glass vial, 25 g/glass vial, 100 g/HDPE bottle with desiccant, or 1 kg/aluminum foil bag |
| Testing Indicators | Appearance — Visual inspection (white to off-white crystalline powder); Melting point — Capillary method (122–126°C, EP/BP); Purity — HPLC-UV (≥98–99.5%, EP/BP/USP); Related substances — HPLC (methimazole and other impurities, EP); Loss on drying — Gravimetric (≤0.5%, EP); Residue on ignition — Gravimetric (≤0.1%, EP); Heavy metals — Colorimetric/ICP-MS (≤20 ppm, EP); Assay — Titrimetric or HPLC (EP/BP/USP); Identification — FTIR (characteristic peaks: C=O ~1740 cm⁻¹, C=S ~1280 cm⁻¹, N–CH₃ ~1450 cm⁻¹); ¹H NMR (CDCl₃: δ 1.30 ppm triplet CH₃CH₂, δ 3.50 ppm singlet N–CH₃, δ 4.20 ppm quartet CH₂); Mass spectrometry — ESI-MS (m/z 187 [M+H]⁺); Water content — Karl Fischer titration (GB/T 6283/EP 2.5.12); pH — Potentiometry (neutral, aqueous suspension). |
| Storage Notes | Store in a cool, dry, well-ventilated area below 25°C. Protect from light, moisture, and air. Keep container tightly sealed under inert atmosphere (nitrogen or argon) if specified. Light-sensitive and moisture-sensitive material; avoid prolonged exposure to light and humid conditions. Store away from strong oxidizing agents and incompatible substances. |
| Lead Time | 10 days |
Carbimazole is a prodrug of methimazole, acting as an inhibitor of thyroid peroxidase. It is used as a pharmaceutical intermediate and API for the treatment of hyperthyroidism (Graves' disease) and preparation for thyroid surgery. In vivo, it is rapidly metabolized to methimazole (MMI), which exerts anti-thyroid activity by blocking iodine incorporation into tyrosine residues and inhibiting thyroxine synthesis. Also employed in analytical method development, method validation (AMV), and quality control (QC) applications for abbreviated new drug applications (ANDA).