18-Crown-5 [4-(2,4-dinitrophenylazo)phenol] CAS 81238-58-6
Purity 97%+In StockPharmaceutical Standards
| CAS No. | 81238-58-6 |
| Molecular Formula | C22H26N4O10 |
| Molecular Weight | 506.46 g/mol |
| Category | Pharmaceutical Standards / API Standards |
| Availability | In Stock |
Chemical Structure
Description
18-Crown-5 [4-(2,4-dinitrophenylazo)phenol] (CAS 81238-58-6) reference standard, produced by CATO (ISO 17034 / CNAS / ANAB accredited). Molecular formula: C22H26N4O10. Molecular weight: 506.46 g/mol. Trusted by 10,000+ laboratories worldwide for pharmaceutical analysis and QC.
Physical & Chemical Properties
| Molecular Formula | C22H26N4O10 |
| Molecular Weight | 506.46 g/mol |
| Appearance | Pale yellow to yellow crystalline powder |
| Purity | 97%+ |
| Storage | Store in a cool place (≤25°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) | 12.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1980 |
| Nitrogen Atoms | 4 |
Related Crown Standards
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- 15-Crown-4[4-(2,4-Dinitrophenylazo)phenol] (CAS 81238-57-5)
- (-)-(18-Crown-6)-2,3,11,12-tetracarboxylic Acid (CAS 73891-15-3)
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- 30-Crown-6 (1,6,11,16,21,26-Hexaoxacyclotriacontane) (CAS 64001-05-4)
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- [21]Crown-7-ether (CAS 33089-36-0)
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Recommended Standards
- (2R,3S,4S,5R,6S)-2-(Acetoxymethyl)-6-((4-methyl-2-oxo-2H-chromen-7-yl)oxy)tetrahydro-2H-pyran-3,4,5-triyl triacetate (CAS 6160-79-8)
- 4-Methylumbelliferyl 2,3,4,6-Tetra-O-acetyl-b-D-glucopyranoside (CAS 67909-25-5)
- 5'-((3,5-Dicarboxyphenyl)ethynyl)-[1,1':3',1''-terphenyl]-4,4''-dicarboxylic acid (CAS 1542480-30-7)
- tert-Butyl (2-cyanopyridin-3-yl)carbamate (CAS 887579-88-6)
- (βR)-β-Amino-3,4-difluorobenzenepropanoic acid (CAS 1241679-26-4)
- 4-Ethoxy-2-isopropyl-5-morpholinopyridazin-3(2H)-one (CAS 51659-92-8)
- 2-(Aminomethyl)-4-iodoaniline (CAS 166883-36-9)
- 2,5-Dihydro-5-oxo-1-phenyl-1H-1,2,4-triazole-3-carboxylic acid (2-chlorophenyl)amide (CAS 1000576-93-1)
- 1,3-Dihydro-1,3-dioxo-2H-isoindol-2-yl 1-methylcyclohexanecarboxylate (CAS 1788861-32-4)
- ([D2]Gly4)-Cholecystokinin Octapeptide (sulfated) ammonium salt (CAS 1926163-74-7)
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