| CAS No. | 1248-18-6 |
| Molecular Formula | C20H13N2O4S |
| Molecular Weight | N/A |
| Category | Pharmaceutical Standards / API Standards |
| Availability | In Stock |
Lithol Red R (CAS 1248-18-6), molecular formula C20H13N2O4SNa and molecular weight 400.38 g/mol, is a CATO reference standard with documented purity and traceability.
Based on its molecular formula C20H13N2O4SNa, Lithol Red R contains a flavonoid core, an amide group, a sulfone group, a hydroxyl group, an ether linkage; these features give the compound characteristic absorption bands in UV spectroscopy. The molecular weight of 400.38 g/mol is directly relevant to the identification of the molecular ion in mass spectrometry. Nitrogen-containing functional groups confer excellent ionization efficiency in positive-ion electrospray (ESI) mode, making the compound well suited to LC-MS/MS analysis.
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.
| Molecular Formula | C20H13N2O4S Na |
| Molecular Weight | 400.38 g/mol |
| Purity | >60% |
| 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) | 15.5 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1957 |
| Nitrogen Atoms | 2 |
| Sulfur Atoms | 1 |