| CAS No. | 34632-04-7 |
| Molecular Formula | C16H17N3O4S |
| Molecular Weight | 347.39 g/mol |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
Under current pharmacopoeial and regulatory frameworks, quality-control requirements for this class of reference material explicitly involve the control of targets including Cephalexin Impurity 18.
Cephalexin Impurity 18 (CAS 34632-04-7) is a certified pharmaceutical impurity reference standard with the molecular formula C16H17N3O4S and a molecular weight of 347.39 g/mol.
Cephalexin Impurity 18 (C16H17N3O4S) contains a flavonoid core, an amide group, a sulfone group, a hydroxyl group, an ether linkage. It is notably hygroscopic, the carboxyl group imparts weak acidity; these physicochemical properties determine the optimal preparation and storage of its standard solutions. 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).
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 Cephalexin Impurity 18 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.
| Molecular Formula | C16H17N3O4S |
| Molecular Weight | 347.39 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 |
| Degree of Unsaturation (DBE) | 10.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1966 |
| Nitrogen Atoms | 3 |
| Sulfur Atoms | 1 |