Levothyroxine Impurity 42 CAS 4618-45-5
| CAS No. | 4618-45-5 |
| Molecular Formula | C13H7I3O4 |
| Molecular Weight | 607.91 g/mol |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
Chemical Structure
Description
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 process- or degradation-related impurity, Levothyroxine Impurity 42 (CAS 4618-45-5, C13H7I3O4) is essential for impurity profiling, related-substances testing, and forced-degradation studies in pharmaceutical development.
Owing to a carboxylic acid group, a hydroxyl group, an ether linkage, iodine substitution, an aromatic ring system, Levothyroxine Impurity 42 is typically pale yellow to yellow amorphous powder. Its solid-state physicochemical attributes — including a molecular weight of 607.91 g/mol — guide the selection of appropriate sample preparation and analytical techniques. The aromatic system may exhibit native fluorescence, enabling detection with a fluorescence detector (FLD).
As a certified reference material (CRM), Levothyroxine Impurity 42 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.
Physical & Chemical Properties
| Molecular Formula | C13H7I3O4 |
| Molecular Weight | 607.91 g/mol |
| Purity | >95% |
| Storage | Store in a cool place (≤25°C), protect from light, keep sealed and dry |
| Solubility (reference) | Soluble in chloroform, dichloromethane, ethyl acetate, DMSO |
| 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) | 9.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1958 |
| Halogen Content | I-containing |
Related Levothyroxine Standards
- Levothyroxine Impurity 16 (CAS 92905-78-7)
- Levothyroxine EP Impurity C (CAS 51-24-1)
- Levothyroxine Impurity 58 (CAS 176258-87-0)
- Levothyroxine Impurity 14 (CAS 3914-31-6)
- Levothyroxine Impurity 17 (CAS 51-26-3)
- Levothyroxine EP Impurity A (CAS 6893-02-3)
- Levothyroxine EP Impurity K (CAS 5817-39-0)
- Levothyroxine EP Impurity K (R-Isomer) (CAS 66701-15-3)
Recommended Standards
- Afoxolaner Impurity 30 (CAS CATO-C4X-313730)
- TRis(1h,1h-heptafluorobutyl)borate (CAS 755-53-3)
- N-Biotinylcaproylaminocaproylaminoethyl methanethiosulfonate, 96% (CAS 1038749-81-3)
- Dipalmitoyl Hydroxyproline (CAS 41672-81-5)
- Linezolid Impurity 15 (CAS 93246-53-8)
- Vonoprazan Fumarate Impurity 26 (CAS CATO-C4X-102026)
- Nemonoxacin Impurity 28 (CAS 951163-63-6)
- 1’-Boc-spiro[indoline-3,4’-piperidin]-2-one (CAS 252882-60-3)
- 4-Fluoro-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-7,8-dihydronaphthalene-2-carbonitrile (CAS 2762504-74-3)
- methyl 3-(chlorosulfonyl)-2-phenylpropanoate (CAS 1803560-95-3)
- 1-(1-Methyl-1H-indol-3-yl)-3-(thiazol-2-yl)urea (CAS 899947-32-1)
- Methyl 5-amino-1H-imidazole-4-carboxylate hydrochloride (CAS 116401-54-8)
- 1,5-dimethyl 2-acetylpentanedioate (CAS 116981-01-2)
- Neuropeptide Y, human (CAS 98264-90-5)
Why CATO?
- ISO 17034 accredited reference material producer (CNAS + ANAB dual accreditation)
- 130,000+ catalog items in stock, COA supplied with every batch
- Worldwide shipping with full export documentation (HS code guidance available)
- Technical support: +86 18665070610 / Nicole.chen@cato-chem.com