Tofacitinib Impurity 141 (Mixture of Tautomeric Isomers) CAS 1245811-22-6
| CAS No. | 1245811-22-6 |
| Molecular Formula | 2*C6H4ClN3O |
| Molecular Weight | N/A |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
Chemical Structure
Description
CATO supplies Tofacitinib Impurity 141 (Mixture of Tautomeric Isomers) (CAS 1245811-22-6), a pharmacopoeial impurity reference standard (molecular formula C6H4ClN3O, MW 169.57 g/mol) used for the identification and quantification of trace impurities in APIs.
Owing to an amide group, a hydroxyl group, an ether linkage, chlorine substitution, an aromatic ring system, Tofacitinib Impurity 141 (Mixture of Tautomeric Isomers) is typically off-white to pale yellow crystalline powder. Its solid-state physicochemical attributes — including a molecular weight of 169.57 g/mol — guide the selection of appropriate sample preparation and analytical techniques. 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).
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 | 2*C6H4ClN3O |
| Molecular Weight | 169.57 g/mol |
| Appearance | Off-white to pale yellow crystalline powder. (slight halide-like odor, faint amine-like odor) |
| Purity | >95% |
| Storage | Store at 2-8°C, protect from light, keep tightly closed to prevent evaporation |
| Solubility (reference) | Soluble in DMSO, DMF, methanol |
| Stability | May oxidize slowly on prolonged air exposure; Light-sensitive; avoid direct strong light |
| Degree of Unsaturation (DBE) | 6.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1990 |
| Halogen Content | Cl-containing |
| Nitrogen Atoms | 3 |
Related Tofacitinib Standards
- Tofacitinib Impurity 180 (CAS 100047-45-8)
- Tofacitinib Impurity 133 (CAS 10132-07-7)
- Tofacitinib Impurity 182 (CAS 1053228-28-6)
- Tofacitinib Impurity 123 DiHCl (CAS 1062580-52-2)
- Tofacitinib Impurity 20 (CAS 1092578-43-2)
- Tofacitinib Impurity 38 (CAS 1092578-45-4)
- Tofacitinib Impurity 1 (CAS 1092578-46-5)
- Tofacitinib Impurity 3 (CAS 1092578-47-6)
Recommended Standards
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- 4-(2-(Pyridin-2-yl)ethyl)aniline (CAS 6318-71-4)
- Kazinol B (CAS 99624-27-8)
- Methyl 2-(1-methylpyrrolidin-2-yl)acetate (CAS 51856-76-9)
- D-Lys16-Tirzepatide (CAS CATO-CPTD788918)
Why CATO?
- ISO 17034 accredited reference material producer (CNAS + ANAB dual accreditation)
- 130,000+ catalog items in stock, COA supplied with every batch
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- Technical support: +86 18665070610 / Nicole.chen@cato-chem.com