4-Amino-2-methylbenzenesulfonic acid CAS 133-78-8
| CAS No. | 133-78-8 |
| Molecular Formula | C7H9NO3S |
| Molecular Weight | 187.22 g/mol |
| Category | Pharmaceutical Standards / API Standards |
| Availability | In Stock |
Chemical Structure
Description
As a certified reference material (CRM), 4-Amino-2-methylbenzenesulfonic acid meets the metrological traceability requirements of ISO/IEC 17025 laboratories. Batch-to-batch consistency is monitored via control charts to guarantee comparable assigned values across lots.
CATO supplies 4-Amino-2-methylbenzenesulfonic acid (CAS 133-78-8), a certified reference material (molecular formula C7H9NO3S, MW 187.22 g/mol) for analytical method development and quality control.
Based on its molecular formula C7H9NO3S, 4-Amino-2-methylbenzenesulfonic acid contains an amide group, a sulfone group, a carboxylic acid group, a hydroxyl group, an ether linkage, an aromatic ring system; these features give the compound characteristic absorption bands in UV spectroscopy. The molecular weight of 187.22 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.
Physical & Chemical Properties
| Molecular Formula | C7H9NO3S |
| Molecular Weight | 187.22 g/mol |
| Purity | 97%+ |
| Storage | Store at 2-8°C, protect from light, keep sealed and dry |
| Solubility (reference) | Soluble in methanol, ethanol, DMSO, water |
| 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 |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1957 |
| Nitrogen Atoms | 1 |
| Sulfur Atoms | 1 |
Related Amino Standards
- Methyl 5-amino-3-(methylthio)-1H-pyrazole-4-carboxylate (CAS 117717-02-9)
- 2-Amino-n-methylpyridine-3-sulfonamide (CAS 1250972-58-7)
- 2-Amino-3-(methylsulfonyl)phenol (CAS 129318-50-9)
- 3-Amino-2,4,6,7-tetrahydrothiopyrano[4,3-c]pyrazole 5,5-dioxide (CAS 1306604-52-3)
- 2-Amino-3-(2-thioxo-2,3-dihydro-1H-imidazol-4-yl)propanoic acid (CAS 13552-61-9)
- 3-Amino-5-methylpyridine-2-sulfonamide (CAS 163137-50-6)
- Ethyl 2-amino-4-hydroxythiophene-3-carboxylate (CAS 16694-23-8)
- 3-Amino-N-methylpyridine-2-sulfonamide (CAS 1698428-16-8)
Recommended Standards
- 2-Methoxy-N-(5-methyl-1,3,4-thiadiazol-2-yl)acetamide (CAS 132214-40-5)
- ethyl 4-hydroxy-5-methyl-1,3-thiazole-2-carboxylate (CAS 133833-93-9)
- 2,6-Diamino-5-propylpyrimidine-4-carboxylic acid (CAS 13166-62-6)
- 1-(Pyrazin-2-yl)ethane-1-sulfonamide (CAS 1342245-69-5)
- Fmoc-N-amido-dPEG <SUP>®</SUP><SUB>8</SUB>-NHS ester (CAS 1334170-03-4)
- 4-Chloro-N-methyl-5-(methylthio)-6-(pyrrolidin-1-yl)pyrimidin-2-amine (CAS 400074-29-5)
- H-Ala-Asp-OH (CAS 21224-60-2)
- (1S,2R)-1-Amino-2-methylcyclopentanecarboxylic acid (CAS 309757-06-0)
- Taletrectinib Impurity7 (CAS 1012344-76-1)
- 1-(4-(Aminomethyl)piperidin-1-yl)-2-ethylhexan-1-one hydrochloride (CAS 1588901-35-2)
- 3-(1-Methylhydrazinyl)benzo[d]isothiazole 1,1-dioxide (CAS 303064-94-0)
- 3-(3,4-Dimethylphenyl)-2-thioxo-4-imidazolidinone (CAS 568552-79-4)
- 5-(3-Fluorophenyl)-1H-indole (CAS 893739-63-4)
- Tirzepatide Impurity 37 (CAS CATO-C4X-324037)
Why CATO?
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