Cholic Acid Impurity 18 CAS 517-33-9
| CAS No. | 517-33-9 |
| Molecular Formula | C24H36O5 |
| Molecular Weight | 404.54 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 Cholic Acid Impurity 18.
CATO supplies Cholic Acid Impurity 18 (CAS 517-33-9), a pharmacopoeial impurity reference standard (molecular formula C24H36O5, MW 404.54 g/mol) used for the identification and quantification of trace impurities in APIs.
Cholic Acid Impurity 18 (C24H36O5) contains a flavonoid core, a hydroxyl group, an ether linkage. 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 | C24H36O5 |
| Molecular Weight | 404.54 g/mol |
| Appearance | Off-white to pale yellow crystalline powder |
| Purity | >95% |
| Storage | Store at room temperature, protect from light, keep sealed and dry |
| Solubility (reference) | Soluble in methanol, acetonitrile, DMSO, water (slightly soluble) |
| Stability | May oxidize slowly on prolonged air exposure; Light-sensitive; avoid direct strong light |
| Degree of Unsaturation (DBE) | 7.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1957 |
Related Cholic Standards
- Cholic Acid Impurity 13 (CAS 2304-92-9)
- Cholic Aicd Impurity 17 (CAS 2304-91-8)
- Cholic Acid Impurity 27 (CAS CATO-C4X-116027)
- Cholic Acid Impurity 28 (CAS CATO-C4X-116028)
- Cholic Acid Impurity 52 (CAS 68170-81-0)
- Cholic Acid impurity 75 (CAS 2862-62-6)
- Cholic Acid Impurity 19 (CAS 2304-89-4)
- Cholic Acid Impurity 78 (CAS 79732-73-3)
Recommended Standards
- Simvastatin EP Impurity E (CAS 75330-75-5)
- Simvastatin EP Impurity F (CAS 79952-44-6)
- Oxazole, 2,2′-[(1S)-6,6′-dimethyl[1,1′-biphenyl]-2,2′-diyl]bis[4,5-dihydro-4-(1-methylethyl)-, (4S,4′S)- (CAS 209003-59-8)
- 6,7-Diketolithocholic Acid (CAS 1643669-23-1)
- Clarithromycin Impurity 35 (CAS CATO-C4X-100235)
- Posaconazole Impurity 167 (CAS CATO-C4X-1208167)
- Propofol Impurity 33 (CAS CATO-C4X-147333)
- 5-Phenyl-4h-1,2,4-triazol-3-amine (CAS 4922-98-9)
- [1,1'-Biphenyl]-2-ylglycine (CAS 39950-18-0)
- 2-((5-Bromopyrimidin-2-yl)oxy)acetic acid (CAS 270912-79-3)
- Mesityl Oxide Epoxide (CAS 142532-81-8)
- 1-(Chlorodifluoromethoxy)-3-fluorobenzene (CAS 147992-30-1)
- Methyl 2-morpholinopyrimidine-5-carboxylate (CAS 930111-21-0)
- Semaglutide impurity 40 (CAS CATO-C4X-222640)
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