| CAS No. | 67-52-7 |
| Molecular Formula | C4H4N2O3 |
| Molecular Weight | 128.09 g/mol |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
The occurrence of Fluorouracil EP Impurity A is closely related to an amino-acid-derived structure, an amide group, a hydroxyl group, an ether linkage in its molecular formula, which determines its behaviour during synthesis, purification, or degradation.
Fluorouracil EP Impurity A (CAS 67-52-7) is a certified pharmaceutical impurity reference standard with the molecular formula C4H4N2O3 and a molecular weight of 128.09 g/mol.
Structurally, Fluorouracil EP Impurity A (C4H4N2O3) contains an amino-acid-derived structure, an amide group, a hydroxyl group, an ether linkage. The molecule exhibits a degree of unsaturation (DBE) of 4.0, corresponding to approximately 4 ring(s) or double-bond equivalent(s). With a molecular weight of 128.09 g/mol, it falls into the low-molecular-weight range. 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.
As a certified reference material (CRM), Fluorouracil EP Impurity A 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.
| Molecular Formula | C4H4N2O3 |
| Molecular Weight | 128.09 g/mol |
| Purity | >95% |
| Storage | Store at 2-8°C, protect from light, keep sealed and dry |
| Solubility (reference) | Soluble in methanol, ethanol, DMSO, water |
| Stability | May oxidize slowly on prolonged air exposure; Light-sensitive; avoid direct strong light; Hygroscopic; reseal immediately after opening |
| Degree of Unsaturation (DBE) | 4.0 |
| UV Absorption | UV-absorbing |
| CAS Registry Year (est.) | 1957 |
| Nitrogen Atoms | 2 |