| CAS No. | 13479-38-4 |
| Molecular Formula | C21H28O4 |
| Molecular Weight | 344.44 g/mol |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
Under current pharmacopoeial and regulatory frameworks, quality-control requirements for this class of reference material explicitly involve the control of targets including Prednisolone EP Impurity I.
Prednisolone EP Impurity I (CAS 13479-38-4) is a certified pharmaceutical impurity reference standard with the molecular formula C21H28O4 and a molecular weight of 344.44 g/mol.
Owing to a flavonoid core, a hydroxyl group, an ether linkage, Prednisolone EP Impurity I is typically pale yellow to yellow crystalline powder. Its solid-state physicochemical attributes — including a molecular weight of 344.44 g/mol — guide the selection of appropriate sample preparation and analytical techniques. The aromatic system may exhibit native fluorescence, enabling detection with a fluorescence detector (FLD).
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 | C21H28O4 |
| Molecular Weight | 344.44 g/mol |
| Appearance | Pale yellow to yellow crystalline powder |
| Purity | >95% |
| Storage | Store at 2-8°C, protect from light, keep sealed and dry |
| Solubility (reference) | Soluble in chloroform, dichloromethane, ethyl acetate, DMSO |
| Stability | May oxidize slowly on prolonged air exposure; Light-sensitive; avoid direct strong light |
| Degree of Unsaturation (DBE) | 8.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1960 |