| CAS No. | 1020252-11-2 |
| Molecular Formula | C18H16BrClN2O2 |
| Molecular Weight | 407.69 g/mol |
| Category | Pharmaceutical Standards / API Standards |
| Availability | In Stock |
This reference standard is suitable for quantitative analysis on major chromatographic platforms including HPLC, GC, LC-MS/MS, and GC-MS, serving as an external calibration standard or a system suitability test reference material.
4-Bromo-5-[(4-chloro-2-methylphenoxy)methyl]-1-methyl-2-phenyl-2,3-dihydro-1H-pyrazol-3-one (CAS 1020252-11-2), molecular formula C18H16BrClN2O2 and molecular weight 407.69 g/mol, is a CATO reference standard with documented purity and traceability.
4-Bromo-5-[(4-chloro-2-methylphenoxy)methyl]-1-methyl-2-phenyl-2,3-dihydro-1H-pyrazol-3-one (C18H16BrClN2O2) contains a steroid core, an amide group, a hydroxyl group, an ether linkage, chlorine/bromine substitution. It is notably hygroscopic, halogen substitution raises its density and boiling point, its high carbon-to-hydrogen ratio confers good lipid solubility, the carboxyl group imparts weak acidity; these physicochemical properties determine the optimal preparation and storage of its standard solutions. Halogen substitution (F/Cl/Br/I) produces a distinctive isotope pattern in mass spectrometry, a valuable aid for qualitative confirmation.
As a certified reference material (CRM), 4-Bromo-5-[(4-chloro-2-methylphenoxy)methyl]-1-methyl-2-phenyl-2,3-dihydro-1H-pyrazol-3-one 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 | C18H16BrClN2O2 |
| Molecular Weight | 407.69 g/mol |
| Appearance | Pale yellow to yellow crystalline powder. (slight halide-like odor, low volatility) |
| Purity | 97%+ |
| Storage | Store in a cool place (≤25°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; Contains ester bond; hydrolyzes under strong alkaline conditions |
| Degree of Unsaturation (DBE) | 11.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1988 |
| Halogen Content | Cl/Br-containing |
| Nitrogen Atoms | 2 |