Thieno[3,2-b]thiophene-2,5-dicarboxylic acid CAS 18646-81-6
| CAS No. | 18646-81-6 |
| Molecular Formula | C8H4O4S2 |
| Molecular Weight | 228.24 g/mol |
| Category | Pharmaceutical Standards / API Standards |
| Availability | In Stock |
Chemical Structure
Description
Thieno[3,2-b]thiophene-2,5-dicarboxylic acid (CAS 18646-81-6) is a high-purity analytical reference standard with the molecular formula C8H4O4S2 and a molecular weight of 228.24 g/mol.
Structurally, Thieno[3,2-b]thiophene-2,5-dicarboxylic acid (C8H4O4S2) contains a sulfone group, a carboxylic acid group, a hydroxyl group, an ether linkage, an aromatic ring system. The molecule exhibits a degree of unsaturation (DBE) of 7.0, corresponding to approximately 7 ring(s) or double-bond equivalent(s). With a molecular weight of 228.24 g/mol, it falls into the medium-molecular-weight range. 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.
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 | C8H4O4S2 |
| Molecular Weight | 228.24 g/mol |
| Purity | 97%+ |
| Storage | Store at 2-8°C, protect from light, keep sealed and dry |
| 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 |
| Degree of Unsaturation (DBE) | 7.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1962 |
| Sulfur Atoms | 2 |
Related Thieno Standards
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- 2-({thieno[2,3-d]pyrimidin-4-yl}amino)propanoic acid (CAS 71635-48-8)
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