| CAS No. | 30923-77-4 |
| Molecular Formula | C18H20N2O2 |
| Molecular Weight | 296.36 g/mol |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
The occurrence of Phenylbutazone Impurity 4 is closely related to a steroid core, an amide group, a hydroxyl group, an ether linkage in its molecular formula, which determines its behaviour during synthesis, purification, or degradation.
As a process- or degradation-related impurity, Phenylbutazone Impurity 4 (CAS 30923-77-4, C18H20N2O2) is essential for impurity profiling, related-substances testing, and forced-degradation studies in pharmaceutical development.
Structurally, Phenylbutazone Impurity 4 (C18H20N2O2) contains a steroid core, an amide group, a hydroxyl group, an ether linkage. The molecule exhibits a degree of unsaturation (DBE) of 10.0, corresponding to approximately 10 ring(s) or double-bond equivalent(s). With a molecular weight of 296.36 g/mol, it falls into the medium-molecular-weight range. 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 | C18H20N2O2 |
| Molecular Weight | 296.36 g/mol |
| Appearance | Pale yellow to yellow crystalline powder |
| 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) | 10.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1965 |
| Nitrogen Atoms | 2 |