| CAS No. | 101386-64-5 |
| Molecular Formula | C21H29NO |
| Molecular Weight | 311.46 g/mol |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
The occurrence of Salmeterol Impurity 18 is closely related to a steroid core, an amide group, a hydroxyl group, an ether linkage in its molecular formula, which determines its behaviour during synthesis, purification, or degradation.
CATO supplies Salmeterol Impurity 18 (CAS 101386-64-5), a pharmacopoeial impurity reference standard (molecular formula C21H29NO, MW 311.46 g/mol) used for the identification and quantification of trace impurities in APIs.
The molecular framework of Salmeterol Impurity 18 (C21H29NO) is characterized by a steroid core, an amide group, a hydroxyl group, an ether linkage. In reversed-phase chromatography, its retention is governed primarily by its high hydrophobicity (logP), which provides a practical basis for HPLC-UV/DAD or LC-MS method development. The high carbon-to-hydrogen ratio imparts good lipophilicity, allowing liquid-liquid extraction with non-polar solvents such as n-hexane or ethyl acetate.
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), Salmeterol Impurity 18 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 | C21H29NO |
| Molecular Weight | 311.46 g/mol |
| Appearance | Pale yellow to yellow crystalline powder |
| Purity | >95% |
| Storage | Store at 2-8°C, protect from light |
| Solubility (reference) | Soluble in chloroform, dichloromethane, ethyl acetate, DMSO |
| Stability | Light-sensitive; avoid direct strong light |
| Degree of Unsaturation (DBE) | 8.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1985 |
| Nitrogen Atoms | 1 |