| CAS No. | 146-21-4 |
| Molecular Formula | C17H20N2OS |
| Molecular Weight | 300.42 g/mol |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
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.
Promazine EP Impurity A (CAS 146-21-4) is a certified pharmaceutical impurity reference standard with the molecular formula C17H20N2OS and a molecular weight of 300.42 g/mol.
The molecular framework of Promazine EP Impurity A (C17H20N2OS) is characterized by a steroid core, an amide group, sulfur-containing functionality, 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 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).
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 | C17H20N2OS |
| Molecular Weight | 300.42 g/mol |
| Purity | 97%+ |
| Storage | Store at 2-8°C, protect from light |
| Solubility (reference) | Soluble in DMSO, DMF, methanol |
| Stability | Light-sensitive; avoid direct strong light |
| Degree of Unsaturation (DBE) | 9.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1957 |
| Nitrogen Atoms | 2 |
| Sulfur Atoms | 1 |