Sildenafil Impurity 51 CAS 263897-18-3
| CAS No. | 263897-18-3 |
| Molecular Formula | C21H28N6O4S |
| Molecular Weight | 460.55 g/mol |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
Chemical Structure
Description
Under current pharmacopoeial and regulatory frameworks, quality-control requirements for this class of reference material explicitly involve the control of targets including Sildenafil Impurity 51.
Sildenafil Impurity 51 (CAS 263897-18-3) is a certified pharmaceutical impurity reference standard with the molecular formula C21H28N6O4S and a molecular weight of 460.55 g/mol.
Based on its molecular formula C21H28N6O4S, Sildenafil Impurity 51 contains a flavonoid core, an amide group, a sulfone group, a hydroxyl group, an ether linkage; these features give the compound characteristic absorption bands in UV spectroscopy. The molecular weight of 460.55 g/mol is directly relevant to the identification of the molecular ion in mass spectrometry. Nitrogen-containing functional groups confer excellent ionization efficiency in positive-ion electrospray (ESI) mode, making the compound well suited to LC-MS/MS analysis.
Recommended for quantitative analysis by HPLC, GC, LC-MS/MS, or GC-MS as an external calibration standard; it can also be used for spiked-recovery experiments, LOD/LOQ determination, and LC-MS/MS multiple-reaction-monitoring (MRM) calibration.
CATO manufactures Sildenafil Impurity 51 under ISO 17034:2016 accreditation with dual CNAS and ANAB accreditation. Each batch is characterized by orthogonal methods and supplied with a full Certificate of Analysis (COA), ensuring metrological traceability.
Physical & Chemical Properties
| Molecular Formula | C21H28N6O4S |
| Molecular Weight | 460.55 g/mol |
| 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 |
| Degree of Unsaturation (DBE) | 11.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 2025 |
| Nitrogen Atoms | 6 |
| Sulfur Atoms | 1 |
Related Sildenafil Standards
- Sildenafil EP Impurity F (CAS 139755-82-1)
- Sildenafil Impurity 30 (CAS 139755-95-6)
- Sildenafil Impurity 303 (CAS CATO-C4X-1128303)
- Sildenafil Impurity 291 (CAS CATO-C4X-1128291)
- Sildenafil Impurity 283 (CAS CATO-C4X-1128283)
- Sildenafil Impurity 10 (CAS 1393816-99-3)
- Sildenafil Impurity 290 (CAS CATO-C4X-1128290)
- Sildenafil Impurity 245 (CAS CATO-C4X-1128245)
Recommended Standards
- Vardenafil Impurity 66 (CAS CATO-C4X-101766)
- Vardenafil EP Impurity A (CAS 2169247-39-4)
- Lubiprostone impurity 5 (CAS CATO-C4X-11365)
- Vardenafil EP impurity A (CAS CATO-C4X-101722)
- Ozanimod Impurity 19 (CAS 2251699-84-8)
- Fluvastatin EP Impurity G (CAS 101125-34-2)
- Upadacitinib Impurity 39 (CAS 2715120-95-7)
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Why CATO?
- ISO 17034 accredited reference material producer (CNAS + ANAB dual accreditation)
- 130,000+ catalog items in stock, COA supplied with every batch
- Worldwide shipping with full export documentation (HS code guidance available)
- Technical support: +86 18665070610 / Nicole.chen@cato-chem.com