Sildenafil EP Impurity F CAS 139755-82-1
| CAS No. | 139755-82-1 |
| Molecular Formula | C21H28N6O4S |
| Molecular Weight | 460.55 g/mol |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
Chemical Structure
Description
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 supplies Sildenafil EP Impurity F (CAS 139755-82-1), a pharmacopoeial impurity reference standard (molecular formula C21H28N6O4S, MW 460.55 g/mol) used for the identification and quantification of trace impurities in APIs.
Based on its molecular formula C21H28N6O4S, Sildenafil EP Impurity F 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. 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 | C21H28N6O4S |
| Molecular Weight | 460.55 g/mol |
| Purity | >95.0% |
| 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.) | 1996 |
| Nitrogen Atoms | 6 |
| Sulfur Atoms | 1 |
Related Sildenafil Standards
- Sildenafil Impurity 51 (CAS 263897-18-3)
- 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)
- Vardenafil EP impurity A (CAS CATO-C4X-101722)
- Vardenafil USP Related Compound E (CAS 448184-46-1)
- Sarpogrelate Impurity 19 (CAS CATO-C4X-291319)
- Dapagliflozin Impurity 140 (CAS 912917-85-2)
- Cefotaxime Impurity 29 (CAS CATO-C4X-120129)
- tert-Butyl 2-(3-bromophenoxy)-2-methylpropanoate (CAS 393186-07-7)
- 2-Chloro-4-cyanobenzenesulfonyl Chloride (CAS 254749-11-6)
- 5-Chloro-3-methoxy-2-propoxybenzaldehyde (CAS 828272-37-3)
- (2-Methyl-benzyl)-(3-trifluoromethylsulfanylpropyl)-amine (CAS 1208080-34-5)
- 4-Acetyl-1H-pyrrole-3-carbaldehyde (CAS 24445-11-2)
- Dexamethasone 21-Palmitate (CAS 14899-36-6)
- Semaglutide Impurity 15 (CAS CATO-C4X-222615)
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