5-Chloro-3-methylisothiazole-4-carboxylic acid CAS 22131-56-2
| CAS No. | 22131-56-2 |
| Molecular Formula | C5H4ClNO2S |
| Molecular Weight | 177.61 g/mol |
| Category | Pharmaceutical Standards / API Standards |
| Availability | In Stock |
Chemical Structure
Description
5-Chloro-3-methylisothiazole-4-carboxylic acid (C5H4ClNO2S) contains an amide group, a sulfone group, a carboxylic acid group, a hydroxyl group, an ether linkage, chlorine substitution. 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. Nitrogen-containing functional groups confer excellent ionization efficiency in positive-ion electrospray (ESI) mode, making the compound well suited to LC-MS/MS analysis.
CATO supplies 5-Chloro-3-methylisothiazole-4-carboxylic acid (CAS 22131-56-2), a certified reference material (molecular formula C5H4ClNO2S, MW 177.61 g/mol) for analytical method development and quality control.
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 | C5H4ClNO2S |
| Molecular Weight | 177.61 g/mol |
| Purity | 97%+ |
| Storage | Store at 2-8°C, protect from light, keep tightly closed to prevent evaporation |
| Solubility (reference) | Soluble in methanol, acetonitrile, DMSO, water (slightly soluble) |
| Stability | May oxidize slowly on prolonged air exposure; Light-sensitive; avoid direct strong light; Contains ester bond; hydrolyzes under strong alkaline conditions |
| Degree of Unsaturation (DBE) | 4.0 |
| UV Absorption | UV-absorbing |
| CAS Registry Year (est.) | 1963 |
| Halogen Content | Cl-containing |
| Nitrogen Atoms | 1 |
| Sulfur Atoms | 1 |
Related Chloro Standards
- 2-Chloro-5-methylthiazole-4-carboxylic Acid (CAS 1194374-24-7)
- 2-(5-Chloro-1,3-thiazol-2-yl)acetic acid (CAS 1363381-03-6)
- (4-Chloro-thiazol-2-yl)acetic acid (CAS 29676-72-0)
- 2-chloro-4-methyl-1,3-thiazole-5-carboxylic acid (CAS 40003-48-3)
- 4-Chloro-2-methoxythiazole-5-carbaldehyde (CAS 866329-04-6)
- 4-Chloro-2-methylthiazole-5-carboxylic acid (CAS 933687-06-0)
- 4-Chloro-3-methoxy-1,2-thiazole-5-carbaldehyde (CAS 2089257-62-3)
- Methyl 2-chloro-1,3-thiazole-4-carboxylate (CAS 850429-61-7)
Recommended Standards
- 6-Chloropyridine-3-sulfinic acid (CAS 99903-02-3)
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- 2-Amino-4-chlorothiophene-3-carboxylic acid (CAS 90312-16-6)
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- 1-(3-Bromopyridin-2-yl)-N,N-dimethylpiperidin-4-amine (CAS 1248083-17-1)
- (1,1-Dioxidobenzo[d]isothiazol-3-yl)-l-phenylalanine (CAS 869651-65-0)
- 3-Methylquinazoline-2,4(1h,3h)-dione (CAS 607-19-2)
- 2-thiocyanatocyclohex-1-enecarbaldehyde (CAS 42141-25-3)
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- Insulin Degludec Impurity 10 (CAS CATO-C4X-215710)
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