Sildenafil Impurity 9 CAS 139756-31-3
| CAS No. | 139756-31-3 |
| Molecular Formula | C16H17ClN4O4S |
| Molecular Weight | 396.85 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 Impurity 9 (CAS 139756-31-3), a pharmacopoeial impurity reference standard (molecular formula C16H17ClN4O4S, MW 396.85 g/mol) used for the identification and quantification of trace impurities in APIs.
Based on its molecular formula C16H17ClN4O4S, Sildenafil Impurity 9 contains a flavonoid core, an amide group, a sulfone group, a hydroxyl group, an ether linkage, chlorine substitution; these features give the compound characteristic absorption bands in UV spectroscopy. The molecular weight of 396.85 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.
CATO manufactures Sildenafil Impurity 9 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 | C16H17ClN4O4S |
| Molecular Weight | 396.85 g/mol |
| Purity | >90% |
| Storage | Store at 2-8°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) | 10.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1996 |
| Halogen Content | Cl-containing |
| Nitrogen Atoms | 4 |
| Sulfur Atoms | 1 |
Related Sildenafil Standards
- Sildenafil EP Impurity D (CAS 1357931-55-5)
- Sildenafil Impurity 27 (CAS 372089-76-4)
- Sildenafil Impurity 45 (CAS 1391054-00-4)
- Sildenafil Impurity 76 (CAS CATO-C4X-112876)
- Sildenafil Impurity 5 (CAS 1058653-74-9)
- Sildenafil Impurity 38 (CAS 319491-68-4)
- Sildenafil Impurity 15 (CAS 2512206-40-3)
- Sildenafil Impurity 269 (CAS CATO-C4X-1128269)
Recommended Standards
- Avanafil Impurity 131 (CAS CATO-C4X-1118131)
- 2-((2-Chlorobenzyl)thio)-4-(trifluoromethyl)-6,7,8,9-tetrahydro-5H-cyclohepta[b]pyridine-3-carbonitrile (CAS 626227-53-0)
- N-(4-Chlorophenyl)-3-(thiophene-2-carboxamido)benzofuran-2-carboxamide (CAS 887896-19-7)
- Eszopiclone-d8 (CAS 1093385-24-0)
- Telmisartan EP Impurity E (CAS 884330-12-5)
- Arotinolol Impurity 64 (CAS CATO-C4X-185464)
- Piracetam Impurity 45 (CAS CATO-C4X-123545)
- 1-(4-Amino-1,2,5-oxadiazol-3-yl)-5-(pyrrolidin-1-ylmethyl)-1H-1,2,3-triazole-4-carboxylic acid (CAS 352446-61-8)
- 5-Chloro-2-methyl-2,3-dihydro-1H-inden-1-one (CAS 64220-40-2)
- 2-Iodo-4-(5-(4-methylpiperazin-1-yl)-1H,1'H-[2,5'-bibenzo[d]imidazol]-2'-yl)phenol (CAS 106050-84-4)
- 3,4-Dibromo-1H-indazole-6-carboxylic acid (CAS 885523-51-3)
- (1R)-1-(thiophen-3-yl)ethan-1-ol (CAS 153035-65-5)
- Topicamide lmpurity 9 (CAS CATO-C4X-21509)
- Human glucagon CRS (CAS 9007-92-5)
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