| CAS No. | 115093-90-8 |
| Molecular Formula | C6H3Cl2N3 |
| Molecular Weight | 188.01 g/mol |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
Compared with other compounds in its class, the molecular weight of 188.01 g/mol gives Tofacitinib Impurity 183 distinctive chromatographic separation conditions and mass-spectrometry parameter settings.
Tofacitinib Impurity 183 (CAS 115093-90-8) is a certified pharmaceutical impurity reference standard with the molecular formula C6H3Cl2N3 and a molecular weight of 188.01 g/mol.
The molecular framework of Tofacitinib Impurity 183 (C6H3Cl2N3) is characterized by a nitrile group, chlorine substitution, an aromatic ring system. In reversed-phase chromatography, its retention is governed primarily by the protonation state of its nitrogen-containing groups, which provides a practical basis for HPLC-UV/DAD or LC-MS method development. Nitrogen-containing functional groups confer excellent ionization efficiency in positive-ion electrospray (ESI) mode, making the compound well suited to LC-MS/MS analysis.
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.
The assigned purity is verified by mass-balance and quantitative NMR (qNMR) approaches, with the expanded uncertainty reported at a 95% confidence level (k=2). Batch homogeneity and stability are independently assessed for every lot.
| Molecular Formula | C6H3Cl2N3 |
| Molecular Weight | 188.01 g/mol |
| Appearance | Off-white to pale yellow crystalline powder. (slight halide-like odor, faint amine-like odor, low volatility) |
| Purity | >95% |
| Storage | Store at 2-8°C, protect from light, keep tightly closed to prevent evaporation |
| Solubility (reference) | Soluble in DMSO, DMF, methanol |
| Stability | May oxidize slowly on prolonged air exposure; Light-sensitive; avoid direct strong light |
| Degree of Unsaturation (DBE) | 6.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1989 |
| Halogen Content | Cl-containing |
| Nitrogen Atoms | 3 |