4-Ethynyl-1H-pyrazole CAS 57121-49-0
| CAS No. | 57121-49-0 |
| Molecular Formula | C5H4N2 |
| Molecular Weight | 92.10 g/mol |
| Category | Pharmaceutical Standards / API Standards |
| Availability | In Stock |
Chemical Structure
Description
Under current pharmacopoeial and regulatory frameworks, quality-control requirements for this class of reference material explicitly involve the control of targets including 4-Ethynyl-1H-pyrazole.
CATO supplies 4-Ethynyl-1H-pyrazole (CAS 57121-49-0), a certified reference material (molecular formula C5H4N2, MW 92.10 g/mol) for analytical method development and quality control.
The molecular framework of 4-Ethynyl-1H-pyrazole (C5H4N2) is characterized by a nitrile group. 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. 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.
As a certified reference material (CRM), 4-Ethynyl-1H-pyrazole 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.
Physical & Chemical Properties
| Molecular Formula | C5H4N2 |
| Molecular Weight | 92.10 g/mol |
| Purity | 97%+ |
| Storage | Store at 2-8°C, protect from light |
| Solubility (reference) | Soluble in DMSO, DMF, methanol |
| Stability | Light-sensitive; avoid direct strong light |
| Degree of Unsaturation (DBE) | 5.0 |
| UV Absorption | UV-absorbing |
| CAS Registry Year (est.) | 1973 |
| Nitrogen Atoms | 2 |
Related Ethynyl Standards
- 1-Ethynyl-1H-pyrazole (CAS 103244-40-2)
- 1-Ethynyl-1H-imidazole (CAS 1197210-75-5)
- 2-Ethynyl-1H-imidazole (CAS 57121-47-8)
- 5-ethynyl-1H-imidazole (CAS 57121-48-9)
- 2-Ethynyl-1H-pyrrole (CAS 67237-51-8)
- 3-Ethynyl-1h-pyrrole (CAS 71580-43-3)
- 5-ethynyl-1H-triazole (CAS 119720-87-5)
- 5-ethynyl-1H-1,2,4-triazole (CAS 2138143-45-8)
Recommended Standards
- 3-Ethynylfuran (CAS 51061-85-9)
- O,O'-(Ethane-1,2-diyl)bis(hydroxylamine) (CAS 5627-11-2)
- 1H-Pyrrole-3-carbonitrile (CAS 7126-38-7)
- 1-Fluoro-2-methylpropan-2-ol (CAS 353-80-0)
- Benzyl (4-aminobicyclo[2.1.1]hexan-1-yl)carbamate (CAS 1355004-67-9)
- 1-(4-Fluorophenyl)-2-oxo-1,2-dihydropyridine-4-carbonitrile (CAS 929000-78-2)
- 2-Cyanoethyl Carbamimidothioate (CAS 57536-15-9)
- Zheda-Phos (CAS 1398565-95-1)
- 2-[(2,4-Dichlorobenzyl)oxy]-3-methoxy-benzoyl chloride (CAS 1160260-33-2)
- (1R)-1-[5-chloro-2-(difluoromethoxy)phenyl]ethan-1-amine hydrochloride (CAS 1384435-42-0)
- Oxazole, 2,2′-cyclopropylidenebis[4,5-dihydro-4-(phenylmethyl)-, (4R,4′R)- (CAS 2634687-72-0)
- 1,2-Bis(trifluoromethyl)-3,6-dibromobenzene (CAS 1806861-02-8)
- 6-Amino-5-methylisoindolin-1-one (CAS 348165-77-5)
- Semaglutide impound 212 (CAS CATO-C4X-2226212)
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