| CAS No. | 6635-20-7 |
| Molecular Formula | C8H7NO5 |
| Molecular Weight | 197.14 g/mol |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
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.
Entacapone Impurity 25 (CAS 6635-20-7) is a certified pharmaceutical impurity reference standard with the molecular formula C8H7NO5 and a molecular weight of 197.14 g/mol.
Based on its molecular formula C8H7NO5, Entacapone Impurity 25 contains an amino-acid-derived structure, an amide group, a hydroxyl group, an ether linkage; these features give the compound characteristic absorption bands in UV spectroscopy. The molecular weight of 197.14 g/mol is directly relevant to the identification of the molecular ion in mass spectrometry. 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.
| Molecular Formula | C8H7NO5 |
| Molecular Weight | 197.14 g/mol |
| Appearance | Off-white to pale yellow crystalline powder. (faint amine-like odor) |
| Purity | >95% |
| Storage | Store at 2-8°C, protect from light, keep sealed and dry |
| Solubility (reference) | Soluble in methanol, ethanol, DMSO |
| Stability | May oxidize slowly on prolonged air exposure; Light-sensitive; avoid direct strong light; Hygroscopic; reseal immediately after opening |
| Degree of Unsaturation (DBE) | 6.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1958 |
| Nitrogen Atoms | 1 |