17153-20-7

Basic information

• Product Name: 3-Methyl-4-isoxazolecarboxylic acid
• Synonyms: AKOS PAO-1630;3-METHYLISOXAZOLE-4-CARBOXYLIC ACID;3-METHYL-4-ISOXAZOLECARBOXYLIC ACID;3-METHYLISOXAZOLE-4-CARBOXYLIC ACID, 98+%;3-Methyl-1,2-oxazole-4-carboxylic acid;3-Methyl-1,2-oxazole-4-carboxylic acid, 4-Carboxy-3-methylisoxazole;3-Methyl-4-Isoxazolecarboxylic Acid(WX614141)
• CAS NO: 17153-20-7
• Molecular Formula: C₅H₅NO₃
• Molecular Weight: 127.1
• EINECS: 1308068-626-2
• Product Categories: Carboxylic Acids;Oxazoles, Isoxazoles & Benzoxazoles;API intermediates;Carboxylic Acids;Oxazoles, Isoxazoles & Benzoxazoles;Heterocycles;Impurities;Intermediates & Fine Chemicals;Pharmaceuticals
• Mol File: 17153-20-7.mol
• Article Data: 2

Chemical Properties

• Melting Point: 185-187°C
• Boiling Point: 303.642 °C at 760 mmHg
• Flash Point: 137.438 °C
• Appearance: white to light yellow crystal powder
• Density: 1.348 g/cm³
• Vapor Pressure: 0.000404mmHg at 25°C
• Refractive Index: 1.514
• Storage Temp.: Keep in dark place,Sealed in dry,Room Temperature
• Solubility: DMSO (Slightly)
• PKA: 2.90±0.25(Predicted)
• BRN: 114157
• CAS DataBase Reference: 3-Methyl-4-isoxazolecarboxylic acid(CAS DataBase Reference)
• NIST Chemistry Reference: 3-Methyl-4-isoxazolecarboxylic acid(17153-20-7)
• EPA Substance Registry System: 3-Methyl-4-isoxazolecarboxylic acid(17153-20-7)

Safety Data

• Hazard Codes: Xi
• Statements: 36/37/38
• Safety Statements: 26-36-36/37/39-22
• Hazardous Substances Data: 17153-20-7(Hazardous Substances Data)

Usage

Chemical Properties

white to light yellow crystal powder

Uses

An impurity in Leflunomide (L322750).

InChI:InChI=1/C5H5NO3/c1-3-4(5(7)8)2-9-6-3/h2H,1H3,(H,7,8)

Upstream product

• 99979-76-7 4-chloromethyl-3-methyl-isoxazole 
• 20328-15-8 3-methylisoxazole-4-carboxylic acid ethyl ester 
• 100367-83-7 (3-methyl-isoxazol-4-yl)-methanol 

Downstream Products

• 62348-18-9 3-methyl-1,2-oxazole-4-carboxylic acid chloride 
• 1079400-46-6 N-(6-amino-5-[2-(trifluoromethoxy)phenyl]pyridin-2-yl)-3-methylisoxazole-4-carboxamide 
• 1079400-31-9 N-(6-amino-5-(2,3,5-trichlorophenyl)pyridin-2-yl)-3-methylisoxazole-4-carboxamide 
• 639523-27-6 3-methyl-isoxazole-4-carboxylic acid [2-(4-methoxy-phenylamino)-phenyl]-amide 
• 1076245-73-2 N-{6-amino-5-[5-ethoxy-2-(trifluoromethoxy)phenyl]pyrazin-2-yl}-3-methylisoxazole-4-carboxamide 
• 1076245-69-6 N-{6-amino-5-[5-fluoro-2-(trifluoromethoxy)phenyl]pyrazin-2-yl}-3-methylisoxazole-4-carboxamide 

Relevant articles and documents

A 3 - substituted - 4 - isoxazole carboxylic acid synthesizing method

The invention relates to a synthesis method of high-purity and high-regioselectivity 3-substituted-4-isoxazole carboxylic acid. The method has the advantages of simplicity and easiness in operation, mild reaction and high yield and can solve the technical problems of harsh reaction conditions, generation of isomers, difficulty in separation, low total yield and difficulty in large-scale production of the existing preparation method. The preparation steps are as follows: taking 3-substituted-3-oxopropionate (I) as a starting raw material, and performing cyclization with hydroxylamine hydrochloride and an alkali in water to prepare 3-substituted-4-isoxazole-5-ketone (II); performing acetalization on the compound (II) and N, N-dimethylformamide dimethyl acetal to prepare 4-dimethylaminomethylene-3-substituted-4-hydrogen-isoxazol-5-ketone (III); performing ring opening by hydrolysis of lactone on the compound (III) in alkaline conditions and re-closing a ring; and acidifying to obtain the 3-substituted-4-isoxazole carboxylic acid. The method for the 3-substituted-4-isoxazole carboxylic acid, provided by the invention, is used for development and large-scale preparation.