Isothiazole Impurity 3 CAS 252004-29-8
| CAS No. | 252004-29-8 |
| Molecular Formula | C18H13N3O3S |
| Molecular Weight | 351.38 g/mol |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
Chemical Structure
Description
Under current pharmacopoeial and regulatory frameworks, quality-control requirements for this class of reference material explicitly involve the control of targets including Isothiazole Impurity 3.
CATO supplies Isothiazole Impurity 3 (CAS 252004-29-8), a pharmacopoeial impurity reference standard (molecular formula C18H13N3O3S, MW 351.38 g/mol) used for the identification and quantification of trace impurities in APIs.
Isothiazole Impurity 3 (C18H13N3O3S) contains a steroid core, an amide group, a sulfone group, a hydroxyl group, an ether linkage. It is notably hygroscopic, 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).
This reference standard supports related-substances testing and method development in line with ICH Q3A/Q3B guidance on impurity control, and is suitable for system suitability testing and forced-degradation studies.
CATO manufactures Isothiazole Impurity 3 under ISO 17034:2016 accreditation with dual CNAS and ANAB accreditation. Each batch is characterized by orthogonal methods and supplied with a full Certificate of Analysis (COA), ensuring metrological traceability.
Physical & Chemical Properties
| Molecular Formula | C18H13N3O3S |
| Molecular Weight | 351.38 g/mol |
| Purity | >95% |
| 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 |
| Degree of Unsaturation (DBE) | 14.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 2025 |
| Nitrogen Atoms | 3 |
| Sulfur Atoms | 1 |
Related Isothiazole Standards
- Isothiazole Impurity 1 (CAS 252004-30-1)
- Isothiazole Impurity 2 (CAS 252004-60-7)
- Ethyl isothiazole-3-carboxylate 1,1-dioxide (CAS 1823946-00-4)
- Isothiazole-4-sulfonyl chloride (CAS 88982-55-2)
- Isothiazole-5-sulfonyl chloride (CAS 362658-19-3)
- Isothiazole-4,5-dicarboxylic acid (CAS 66882-70-0)
- Isothiazole-3,4,5-tricarbonitrile (CAS 857958-14-6)
- Ethyl isothiazole-3-carboxylate (CAS 23244-32-8)
Recommended Standards
- Relebactam Impurity 155 (CAS CATO-C4X-2144155)
- Boc-Thionoala-1-(6-nitro)benzotriazolide (CAS 184951-86-8)
- Relebactam Impurity 154 (CAS CATO-C4X-2144154)
- (2R,6S)-6-(benzyloxymethyl)-4-(tert-butoxycarbonyl)morpholine-2-carboxylic acid (CAS 1093085-91-6)
- Atogepant Impurity 10 (CAS CATO-C4X-328510)
- Ibrutinib Impurity 19 (CAS 1917333-91-5)
- Lidocaine Impurity 91 (CAS CATO-C4X-167991)
- 1-(2-Amino-4-phenylpyridin-3-yl)-2-methylpropan-1-one (CAS 1443286-94-9)
- 4-(Isopentyloxy)-N-(2-phenoxybutyl)aniline (CAS 1040689-26-6)
- 4-(4'-Bromo-[1,1'-biphenyl]-4-yl)-2-methylthiazole (CAS 1421262-90-9)
- 1-Methyl-2-(trifluoromethyl)-1H-indole-5-carbonitrile (CAS 1192152-73-0)
- 3,5-Dimethylbenzaldehyde oxime (CAS 75601-36-4)
- 1-(Tert-butylamino)-3-phenoxypropan-2-ol (CAS 64980-40-1)
- Semaglutide Impurity 121 X Sodium Salt (CAS CATO-C4X-2226121)
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