| CAS No. | CATO-C4X-1079148 |
| Molecular Formula | C20H25N5O2S |
| Molecular Weight | 399.51 g/mol |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
As a certified reference material (CRM), Tofacitinib Impurity 148 meets the metrological traceability requirements of ISO/IEC 17025 laboratories. Batch-to-batch consistency is monitored via control charts to guarantee comparable assigned values across lots.
CATO supplies Tofacitinib Impurity 148 (CAS CATO-C4X-1079148), a pharmacopoeial impurity reference standard (molecular formula C20H25N5O2S, MW 399.51 g/mol) used for the identification and quantification of trace impurities in APIs.
Based on its molecular formula C20H25N5O2S, Tofacitinib Impurity 148 contains a steroid core, an amide group, a sulfone group, a hydroxyl group, an ether linkage; these features give the compound characteristic absorption bands in UV spectroscopy. The molecular weight of 399.51 g/mol is directly relevant to the identification of the molecular ion in mass spectrometry. The presence of an aromatic ring or conjugated system gives the compound characteristic absorption bands in the UV-Vis region, making it well suited to UV or diode-array detection (DAD).
This reference standard supports related-substances testing and method development in line with ICH Q3A/Q3B guidance on impurity control, and is suitable for system suitability testing and forced-degradation studies.
| Molecular Formula | C20H25N5O2S |
| Molecular Weight | 399.51 g/mol |
| Purity | 97%+ |
| Storage | Store at 2-8°C, protect from light, keep sealed and dry |
| Solubility (reference) | Soluble in DMSO, DMF, methanol |
| Stability | May oxidize slowly on prolonged air exposure; Light-sensitive; avoid direct strong light; Hygroscopic; reseal immediately after opening |
| Degree of Unsaturation (DBE) | 11.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| Nitrogen Atoms | 5 |
| Sulfur Atoms | 1 |