7-Carboxy-5-chloro-8-hydroxy-3,4-dihydro-3-methylisocoumarin CAS 16281-39-3
| CAS No. | 16281-39-3 |
| Molecular Formula | C11H9ClO5 |
| Molecular Weight | 256.64 g/mol |
| Category | Pharmaceutical Standards / API Standards |
| 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 7-Carboxy-5-chloro-8-hydroxy-3,4-dihydro-3-methylisocoumarin.
7-Carboxy-5-chloro-8-hydroxy-3,4-dihydro-3-methylisocoumarin (CAS 16281-39-3), molecular formula C11H9ClO5 and molecular weight 256.64 g/mol, is a CATO reference standard with documented purity and traceability.
7-Carboxy-5-chloro-8-hydroxy-3,4-dihydro-3-methylisocoumarin (C11H9ClO5) contains a carboxylic acid group, a hydroxyl group, an ether linkage, chlorine substitution, an aromatic ring system. It is notably hygroscopic, halogen substitution raises its density and boiling point, the carboxyl group imparts weak acidity; these physicochemical properties determine the optimal preparation and storage of its standard solutions. 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 analytical method development and validation; each product is supplied with a full Certificate of Analysis (COA) ensuring ISO 17034 metrological traceability.
As a certified reference material (CRM), 7-Carboxy-5-chloro-8-hydroxy-3,4-dihydro-3-methylisocoumarin meets the metrological traceability requirements of ISO/IEC 17025 laboratories. Batch-to-batch consistency is monitored via control charts to guarantee comparable assigned values across lots.
Physical & Chemical Properties
| Molecular Formula | C11H9ClO5 |
| Molecular Weight | 256.64 g/mol |
| Appearance | Off-white to pale yellow crystalline powder. (slight halide-like odor) |
| Purity | 97%+ |
| Storage | Store at 2-8°C, protect from light, keep sealed and dry, keep tightly closed to prevent evaporation |
| Solubility (reference) | Soluble in methanol, ethanol, DMSO |
| Stability | May oxidize slowly on prolonged air exposure; Light-sensitive; avoid direct strong light; Hygroscopic; reseal immediately after opening; Contains ester bond; hydrolyzes under strong alkaline conditions |
| Degree of Unsaturation (DBE) | 7.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1961 |
| Halogen Content | Cl-containing |
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