5-Methoxy-2-thioxo-2,3-dihydropyrimidin-4(1H)-one CAS 6939-11-3
| CAS No. | 6939-11-3 |
| Molecular Formula | C5H6N2O2S |
| Molecular Weight | 158.18 g/mol |
| Category | Pharmaceutical Standards / API Standards |
| Availability | In Stock |
Chemical Structure
Description
5-Methoxy-2-thioxo-2,3-dihydropyrimidin-4(1H)-one (CAS 6939-11-3), molecular formula C5H6N2O2S and molecular weight 158.18 g/mol, is a CATO reference standard with documented purity and traceability.
Owing to an amide group, a sulfone group, a carboxylic acid group, a hydroxyl group, an ether linkage, 5-Methoxy-2-thioxo-2,3-dihydropyrimidin-4(1H)-one is typically off-white to pale yellow crystalline powder. Its solid-state physicochemical attributes — including a molecular weight of 158.18 g/mol — guide the selection of appropriate sample preparation and analytical techniques. 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).
This reference standard is suitable for quantitative analysis on major chromatographic platforms including HPLC, GC, LC-MS/MS, and GC-MS, serving as an external calibration standard or a system suitability test reference material.
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 | C5H6N2O2S |
| Molecular Weight | 158.18 g/mol |
| Purity | 97%+ |
| Storage | Store at 2-8°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) | 4.0 |
| UV Absorption | UV-absorbing |
| CAS Registry Year (est.) | 1958 |
| Nitrogen Atoms | 2 |
| Sulfur Atoms | 1 |
Related Methoxy Standards
- 5-Methoxy-2-thiophenecarboxylic Acid (CAS 29212-22-4)
- 2-Methoxy-1-(tetrahydro-2H-pyran-4-yl)ethan-1-one (CAS 1338948-04-1)
- 5-Methoxy-4-oxaspiro[2.5]octan-7-ol (CAS 1359869-20-7)
- 1-Methoxy-5-methylhexane-2,4-dione (CAS 144712-26-5)
- 2-Methoxy-1-(oxan-3-yl)ethan-1-one (CAS 1528714-77-3)
- 2-Methoxy-2-(oxan-4-yl)acetaldehyde (CAS 1820747-67-8)
- 5-Methoxy-5-methylhexane-2,4-dione (CAS 65923-86-6)
- 2-ethyl-5-methoxy-2,3-dihydropyridazin-3-one (CAS 1262423-58-4)
Recommended Standards
- 5-Methyl-1,2,3-thiadiazole-4-carbohydrazide (CAS 4137-63-7)
- 5-Mercapto-2-methyloxazole-4-carboxamide (CAS 83990-20-9)
- 5-Thioxohexahydroimidazo[4,5-d]imidazol-2(1H)-one (CAS 75371-25-4)
- 5-Hydroxy-6-methyl-2-thioxo-2,3-dihydropyrimidin-4(1H)-one (CAS 35463-39-9)
- {4-[2-(4-chlorophenoxy)ethoxy]phenyl}methanamine (CAS 938321-02-9)
- 2-(((4-Chlorobenzyl)oxy)amino)pyrimidine-5-carbonitrile (CAS 400085-97-4)
- N-(benzo[d][1,3]dioxol-5-yl)piperidin-4-amine (CAS 245057-69-6)
- D-6-Hydroxynorleucine (CAS 16509-61-8)
- 2-Cyclohexyl-2-{[(5E)-5-[(furan-2-yl)methylidene]-4-oxo-4,5-dihydro-1,3-thiazol-2-yl]amino}acetic acid (CAS 1007980-93-9)
- 3-amino-1-(4-methylphenyl)pyrrolidin-2-one (CAS 6103-50-0)
- Carbamothioylmethyl acetate (CAS 40235-62-9)
- (S)-1-(3-fluoro-4-methoxyphenyl)-2-methylpropan-1-amine (CAS 1212972-73-0)
- 2,4-Difluorophenylsulfonylethanol (CAS 688763-15-7)
- Acetyl Tetrapeptide-5 (CAS 820959-17-9)
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