Mesalazine EP Impurity L CAS 118-91-2
| CAS No. | 118-91-2 |
| Molecular Formula | C7H5ClO2 |
| Molecular Weight | 156.57 g/mol |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
Chemical Structure
Description
CATO supplies Mesalazine EP Impurity L (CAS 118-91-2), a pharmacopoeial impurity reference standard (molecular formula C7H5ClO2, MW 156.57 g/mol) used for the identification and quantification of trace impurities in APIs.
The molecular framework of Mesalazine EP Impurity L (C7H5ClO2) is characterized by a carboxylic acid group, a hydroxyl group, an ether linkage, chlorine substitution, an aromatic ring system. In reversed-phase chromatography, its retention is governed primarily by the polarity and ionization state of its functional groups, which provides a practical basis for HPLC-UV/DAD or LC-MS method development. Halogen substitution (F/Cl/Br/I) produces a distinctive isotope pattern in mass spectrometry, a valuable aid for qualitative confirmation.
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 | C7H5ClO2 |
| Molecular Weight | 156.57 g/mol |
| Appearance | Off-white to pale yellow crystalline powder. (slight halide-like odor) |
| Purity | >95% |
| Storage | Store at 2-8°C, keep tightly closed to prevent evaporation |
| Solubility (reference) | Soluble in methanol, acetonitrile, DMSO, water (slightly soluble) |
| Stability | May oxidize slowly on prolonged air exposure; Contains ester bond; hydrolyzes under strong alkaline conditions |
| Degree of Unsaturation (DBE) | 5.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1957 |
| Halogen Content | Cl-containing |
Related Mesalazine Standards
Recommended Standards
- Bupropion Impurity 49 (CAS 535-80-8)
- Tizanidine Impurity 52 (CAS CATO-C4X-144552)
- Lenvatinib Impurity 25（Phenyl Chloroformate） (CAS 1885-14-9)
- Indometacin EP Impurity A (CAS 74-11-3)
- Bilastine impurity 79 (CAS 2199440-15-6)
- Stiripentol Impurity 5 (CAS 30024-74-9)
- Resmetirom impurity 86 (CAS CATO-C4X-291286)
- Lemborexant Impurity 88 (CAS CATO-C4X-304288)
- 1-(4-chlorophenyl)-2,2-difluoroethan-1-ol 170653-43-7 (CAS 170653-43-7)
- 6-Hydroxy-6-methyl-2-thiaspiro[3.3]Heptane 2,2-dioxide (CAS 2411634-74-5)
- 1,1,1-Trifluoro-4-(phenylamino)butan-2-ol (CAS 439109-74-7)
- 2-(2-Acetyl-4,5-dimethoxyphenyl)acetic acid (CAS 38210-84-3)
- 2-Bromo-1-[2-(methylsulfonyl)phenyl]ethanone (CAS 99513-18-5)
- Liraglutide Impurity 28 (CAS CATO-C4X-199228)
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