Norfloxacin Impurity 21 CAS 103240-27-3
| CAS No. | 103240-27-3 |
| Molecular Formula | C20H24FN3O4 |
| Molecular Weight | 389.42 g/mol |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
Chemical Structure
Description
Compared with other compounds in its class, the molecular weight of 389.42 g/mol gives Norfloxacin Impurity 21 distinctive chromatographic separation conditions and mass-spectrometry parameter settings.
CATO supplies Norfloxacin Impurity 21 (CAS 103240-27-3), a pharmacopoeial impurity reference standard (molecular formula C20H24FN3O4, MW 389.42 g/mol) used for the identification and quantification of trace impurities in APIs.
Norfloxacin Impurity 21 (C20H24FN3O4) contains a flavonoid core, an amide group, a hydroxyl group, an ether linkage, fluorine substitution. It is notably hygroscopic, halogen substitution raises its density and boiling point, the carboxyl group imparts weak acidity; these physicochemical properties determine the optimal preparation and storage of its standard solutions. The aromatic system may exhibit native fluorescence, enabling detection with a fluorescence detector (FLD).
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.
Physical & Chemical Properties
| Molecular Formula | C20H24FN3O4 |
| Molecular Weight | 389.42 g/mol |
| Appearance | Pale yellow to yellow crystalline powder. (slight halide-like odor) |
| Purity | 97%+ |
| 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; Contains ester bond; hydrolyzes under strong alkaline conditions |
| Degree of Unsaturation (DBE) | 10.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1986 |
| Halogen Content | F-containing |
| Nitrogen Atoms | 3 |
Related Norfloxacin Standards
- Norfloxacin EP Impurity H (CAS 105440-01-5)
- Norfloxacin Impurity 54 (CAS CATO-C4X-146854)
- Norfloxacin Impurity 55 (CAS CATO-C4X-146855)
- Norfloxacin Impurity 20 (CAS CATO-C4X-146820)
- Norfloxacin Impurity 62 (CAS CATO-C4X-146862)
- Norfloxacin Impurity 41 (CAS CATO-C4X-146841)
- Norfloxacin Impurity 51 (CAS CATO-C4X-146851)
- Norfloxacin Impurity 56 (CAS CATO-C4X-146856)
Recommended Standards
- Levofloxacin Impurity 84 (CAS CATO-C4X-137184)
- Ofloxacin Impurity 10 (CAS 107884-32-2)
- Levofloxacin Impurity 38 (CAS 2130840-92-3)
- Balofloxacin (CAS 127294-70-6)
- Daprodustat impurity 2 (CAS CATO-C4X-24072)
- Varenicline Impurity 34 (CAS CATO-C4X-196234)
- Upadacitinib Impurity 147 (CAS CATO-C4X-2405147)
- n-(Cyclopropylmethyl)-1-(2,4-dichlorophenyl)ethan-1-amine (CAS 1019612-07-7)
- Clofarabine Impurity 4 (CAS CATO-C4X-15934)
- Rupintrivir (CAS 223537-30-2)
- N-((3R,4R,5S,6R)-2,4,5-trihydroxy-6-((((2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)oxy)methyl)tetrahydro-2H-pyran-3-yl)acetamide (CAS 50787-10-5)
- 5-Bromo-7-chloro-1-(triisopropylsilyl)-1H-pyrrolo[2,3-c]pyridine (CAS 1198096-80-8)
- (Cis-3-(2,6-diamino-9H-purin-9-yl)cyclopentyl)methanol (CAS 120330-36-1)
- Semaglutide impurity 49 (CAS CATO-C4X-222649)
Why CATO?
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