4-Chloro-2-methylisothiazol-3(2H)-one CAS 71091-90-2
| CAS No. | 71091-90-2 |
| Molecular Formula | C4H4ClNOS |
| Molecular Weight | 149.60 g/mol |
| Category | Pharmaceutical Standards / API Standards |
| Availability | In Stock |
Chemical Structure
Description
Recommended for analytical method development and validation; each product is supplied with a full Certificate of Analysis (COA) ensuring ISO 17034 metrological traceability.
4-Chloro-2-methylisothiazol-3(2H)-one (CAS 71091-90-2) is a high-purity analytical reference standard with the molecular formula C4H4ClNOS and a molecular weight of 149.60 g/mol.
The molecular framework of 4-Chloro-2-methylisothiazol-3(2H)-one (C4H4ClNOS) is characterized by an amide group, sulfur-containing functionality, a hydroxyl group, an ether linkage, chlorine substitution. In reversed-phase chromatography, its retention is governed primarily by the protonation state of its nitrogen-containing groups, which provides a practical basis for HPLC-UV/DAD or LC-MS method development. Halogen substitution (F/Cl/Br/I) produces a distinctive isotope pattern in mass spectrometry, a valuable aid for qualitative confirmation.
CATO manufactures 4-Chloro-2-methylisothiazol-3(2H)-one under ISO 17034:2016 accreditation with dual CNAS and ANAB accreditation. Each batch is characterized by orthogonal methods and supplied with a full Certificate of Analysis (COA), ensuring metrological traceability.
Physical & Chemical Properties
| Molecular Formula | C4H4ClNOS |
| Molecular Weight | 149.60 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 |
| Degree of Unsaturation (DBE) | 3.0 |
| UV Absorption | UV-absorbing |
| CAS Registry Year (est.) | 1977 |
| Halogen Content | Cl-containing |
| Nitrogen Atoms | 1 |
| Sulfur Atoms | 1 |
Related Chloro Standards
- (5-Chloro-1,3,4-thiadiazol-2-yl)methanamine (CAS 1935236-26-2)
- 4-Chloro-3-methoxyisothiazole (CAS 78383-41-2)
- 5-Chloro-3-(methylthio)-1H-1,2,4-triazole (CAS 51108-40-8)
- 5-Chloro-N-methyl-1,3,4-thiadiazol-2-amine (CAS 68429-94-7)
- 5-Chloro-2-Methyl-4-Isothiazolin-3-One (CAS 26172-55-4)
- 4-chloro-N-methyl-3-oxo-butanamide (CAS 1314919-68-0)
- 2-Chloro-1-(3-hydroxy-1-azetidinyl)ethanone (CAS 1628263-61-5)
- 3-Chloro-4-hydroxypiperidin-2-one (CAS 174204-83-2)
Recommended Standards
- (5-Chlorothiazol-2-yl)methanol (CAS 50398-78-2)
- (2-Chlorothiazol-4-yl)methanol (CAS 5198-85-6)
- 5-(Chloromethyl)-1,3,4-thiadiazol-2-amine (CAS 62774-00-9)
- (5-Chlorothiazol-4-yl)methanol (CAS 1934835-38-7)
- 2-[(4-benzoylphenoxy)methyl]oxirane (CAS 19533-07-4)
- Meclizine Dihydrochloride Monohydrate (CAS 31884-77-2)
- 4-Nitrobenzyl (5R,6S)-3-((2-aminoethyl)thio)-6-((R)-1-hydroxyethyl)-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate--1-methylpyrrolidin-2-one hydrochloride (CAS 442847-66-7)
- Tert-butyl 4-hydroxy-3,4-dihydropyridine-1(2H)-carboxylate (CAS 643759-64-2)
- 1-(4-Nitrophenoxy)naphthalene (CAS 3402-81-1)
- N-[4-(1-Azepanylsulfonyl)phenyl]-2-bromoacetamide (CAS 1138445-68-7)
- 3-Methyl-2-(4-oxobenzo[d][1,2,3]triazin-3(4H)-yl)butanoic acid (CAS 105234-47-7)
- tert-Butyl (2-((furan-2-ylmethyl)amino)-2-oxoethyl)carbamate (CAS 1646617-15-3)
- 4-Nitro-1-naphthaldehyde (CAS 42758-54-3)
- Semaglutide Impurity 164 (CAS CATO-C4X-2226164)
Why CATO?
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