| CAS No. | 26889-93-0 |
| Molecular Formula | C16H19N3O5S |
| Molecular Weight | 365.40 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 Amoxicillin EP impurity B.
Amoxicillin EP impurity B (CAS 26889-93-0) is a certified pharmaceutical impurity reference standard with the molecular formula C16H19N3O5S and a molecular weight of 365.40 g/mol.
Structurally, Amoxicillin EP impurity B (C16H19N3O5S) contains a flavonoid core, an amide group, a sulfone group, a hydroxyl group, an ether linkage. The molecule exhibits a degree of unsaturation (DBE) of 9.0, corresponding to approximately 9 ring(s) or double-bond equivalent(s). With a molecular weight of 365.40 g/mol, it falls into the moderately-high-molecular-weight range. 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.
As a certified reference material (CRM), Amoxicillin EP impurity B meets the metrological traceability requirements of ISO/IEC 17025 laboratories. Batch-to-batch consistency is monitored via control charts to guarantee comparable assigned values across lots.
| Molecular Formula | C16H19N3O5S |
| Molecular Weight | 365.40 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) | 9.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1964 |
| Nitrogen Atoms | 3 |
| Sulfur Atoms | 1 |