| CAS No. | 2725318-34-1 |
| Molecular Formula | C22H26N2O10S2 |
| Molecular Weight | N/A |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
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.
Sildenafil impurity 264 (CAS 2725318-34-1) is a certified pharmaceutical impurity reference standard with the molecular formula C22H26N2O10S2C8H19N and a molecular weight of 671.82 g/mol.
Structurally, Sildenafil impurity 264 (C22H26N2O10S2C8H19N) contains a nitrogen-containing heterocyclic scaffold, an amide group, a sulfone group, a hydroxyl group, an ether linkage. The molecule exhibits a degree of unsaturation (DBE) of 10.0, corresponding to approximately 10 ring(s) or double-bond equivalent(s). With a molecular weight of 671.82 g/mol, it falls into the high-molecular-weight range. Nitrogen-containing functional groups confer excellent ionization efficiency in positive-ion electrospray (ESI) mode, making the compound well suited to LC-MS/MS analysis.
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.
| Molecular Formula | C22H26N2O10S2 C8H19N |
| Molecular Weight | 671.82 g/mol |
| Purity | 97%+ |
| 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) | 10.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 2002 |
| Nitrogen Atoms | 3 |
| Sulfur Atoms | 2 |