| CAS No. | CATO-C4X-136743 |
| Molecular Formula | C14H22N2O4 |
| Molecular Weight | 282.34 g/mol |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
The occurrence of Metoprolol Impurity 43 is closely related to a nitrogen-containing heterocyclic scaffold, an amide group, a hydroxyl group, an ether linkage in its molecular formula, which determines its behaviour during synthesis, purification, or degradation.
CATO supplies Metoprolol Impurity 43 (CAS CATO-C4X-136743), a pharmacopoeial impurity reference standard (molecular formula C14H22N2O4, MW 282.34 g/mol) used for the identification and quantification of trace impurities in APIs.
Metoprolol Impurity 43 (C14H22N2O4) contains a nitrogen-containing heterocyclic scaffold, an amide 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.
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 | C14H22N2O4 |
| Molecular Weight | 282.34 g/mol |
| Appearance | Off-white to pale yellow crystalline powder |
| Purity | >95% |
| 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) | 5.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| Nitrogen Atoms | 2 |