1-(5-Methylisoxazol-3-yl)urea CAS 55808-26-9
| CAS No. | 55808-26-9 |
| Molecular Formula | C5H7N3O2 |
| Molecular Weight | 141.13 g/mol |
| Category | Pharmaceutical Standards / API Standards |
| Availability | In Stock |
Chemical Structure
Description
Owing to an amino-acid-derived structure, an amide group, a hydroxyl group, an ether linkage, 1-(5-Methylisoxazol-3-yl)urea is typically off-white to pale yellow liquid. Its solid-state physicochemical attributes — including a molecular weight of 141.13 g/mol — guide the selection of appropriate sample preparation and analytical techniques. Nitrogen-containing functional groups confer excellent ionization efficiency in positive-ion electrospray (ESI) mode, making the compound well suited to LC-MS/MS analysis.
1-(5-Methylisoxazol-3-yl)urea (CAS 55808-26-9) is a high-purity analytical reference standard with the molecular formula C5H7N3O2 and a molecular weight of 141.13 g/mol.
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 | C5H7N3O2 |
| Molecular Weight | 141.13 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.) | 1972 |
| Nitrogen Atoms | 3 |
Related Methylisoxazol Standards
- 2-(4-Methylisoxazol-5-yl)acetic acid (CAS 1368187-80-7)
- (3-Ethyl-5-methylisoxazol-4-yl)methanol (CAS 53064-42-9)
- (5-Ethyl-3-methylisoxazol-4-yl)methanol (CAS 60148-44-9)
- 3-(5-Methylisoxazol-3-yl)propan-1-amine (CAS 1000555-94-1)
- 1-(3-Methylisoxazol-5-Yl)Propan-2-Amine (CAS 1207176-27-9)
- (3-Ethyl-5-methylisoxazol-4-yl)methanamine (CAS 1503307-32-1)
- (5-Ethyl-3-methylisoxazol-4-yl)methanamine (CAS 1520426-84-9)
- N-(5-Methylisoxazol-4-yl)acetamide (CAS 100499-63-6)
Recommended Standards
- 1-(5-Amino-1H-1,2,4-triazol-3-yl)guanidine (CAS 45807-05-4)
- 1,1,1-Trifluoropentan-3-amine (CAS 764606-90-8)
- 1-(5-Amino-1,3,4-oxadiazol-2-yl)propan-2-one (CAS 74949-73-8)
- 1,3-Dimethyl-4-nitro-1H-pyrazole (CAS 3920-38-5)
- Methyl 2-(3-mercapto-5-phenyl-4h-1,2,4-triazol-4-yl)acetate (CAS 1038296-88-6)
- (2S,3S)-2-((tert-Butoxycarbonyl)amino)-3-hydroxy-4-methylpentanoic acid (CAS 929198-85-6)
- 7-Chloro-N-(4-(pyrrolidin-1-ylmethyl)pyridin-2-yl)isoquinolin-3-amine (CAS 1204701-70-1)
- [(2,3-Dimethoxyphenyl)methyl](propyl)amine (CAS 893582-80-4)
- Methyl 2-(dimethylamino)pyridine-4-carboxylate (CAS 26156-52-5)
- 4-Methoxy-N-(5-phenyl-1,2,4-thiadiazol-3-yl)benzamide (CAS 690246-34-5)
- Hydroxy Mifepristone (CAS 105012-15-5)
- n-(2,2-Difluoroethyl)-3-iodoaniline (CAS 1184404-75-8)
- 34955-23-2 4-methyl-3-(pyridin-2-yl)-4,5-dihydro-1H-1,2,4-triazole-5-thione (CAS 34955-23-2)
- Hexapeptide-11 (CAS 100684-36-4)
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