Ketoconazole EP Impurity A (and enantiomer) CAS 254912-63-5
| CAS No. | 254912-63-5 |
| Molecular Formula | C26H26Cl2N4O4 |
| Molecular Weight | 529.42 g/mol |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
Chemical Structure
Description
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.
CATO supplies Ketoconazole EP Impurity A (and enantiomer) (CAS 254912-63-5), a pharmacopoeial impurity reference standard (molecular formula C26H26Cl2N4O4, MW 529.42 g/mol) used for the identification and quantification of trace impurities in APIs.
Based on its molecular formula C26H26Cl2N4O4, Ketoconazole EP Impurity A (and enantiomer) contains a steroid core, an amide group, a hydroxyl group, an ether linkage, chlorine substitution; these features give the compound characteristic absorption bands in UV spectroscopy. The molecular weight of 529.42 g/mol is directly relevant to the identification of the molecular ion in mass spectrometry. 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).
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.
Physical & Chemical Properties
| Molecular Formula | C26H26Cl2N4O4 |
| Molecular Weight | 529.42 g/mol |
| Appearance | Pale yellow to yellow crystalline powder. (slight halide-like odor, low volatility) |
| Purity | >95% |
| Storage | Store in a cool place (≤25°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; Contains ester bond; hydrolyzes under strong alkaline conditions |
| Degree of Unsaturation (DBE) | 15.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 2025 |
| Halogen Content | Cl-containing |
| Nitrogen Atoms | 4 |
Related Ketoconazole Standards
- Ketoconazole Impurity 26 (CAS CATO-C4X-147226)
- Ketoconazole EP Impurity C (and enantiomer) (CAS 83374-59-8)
- Ketoconazole (CAS 65277-42-1)
- Ketoconazole-d8 (CAS 1217706-96-1)
- Ketoconazole impurity 27 (CAS CATO-C4X-147227)
- Ketoconazole impurity 33 (CAS CATO-C4X-147233)
- Ketoconazole N-Oxide (and enantiomer) (CAS 254912-65-7)
- Ketoconazole N-Oxide (CAS 1392277-16-5)
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- M700F048 (CAS 2056235-51-7)
- Ethyl 2-(2-((2,6-dichlorobenzyl)sulfonyl)-4,5-diphenyl-1H-imidazol-1-yl)acetate (CAS 339277-42-8)
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- Larotrectinib Impurity 12 (CAS CATO-C4X-238012)
- (3-Methylbenzyl)hydrazine (CAS 51421-18-2)
- 1-(2,3-Difluorophenyl)-2,2,2-trifluoroethan-1-one (CAS 1092712-21-4)
- 2-Methyl-5-phenyl-1,3-thiazole-4-sulfonamide (CAS 1394041-78-1)
- Calconcarboxylic Acid (CAS 3737-95-9)
- 2-((2,2-Difluorovinyl)oxy)-1-phenylethan-1-amine (CAS 1334148-32-1)
- 2-(4-Chlorophenyl)-4-methylpentane-2,4-diol (CAS 15687-18-0)
- Semaglutide impurity 45 (CAS CATO-C4X-222645)
Why CATO?
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