Isoxazole-5-carboxylic acid
Isoxazole-5-carboxylic acid (CAS: 21169-71-1) is a heterocyclic organic compound with the molecular formula C4H3NO3 and a molecular weight of 113.07 g/mol. It is a white crystalline solid, typically supplied with an assay of 97%. This compound serves as a valuable building block in organic synthesis, particularly in the construction of more complex molecules containing the isoxazole moiety, finding utility in research and development laboratories.

Organic Synthesis Intermediate
Isoxazole-5-carboxylic acid functions as a key intermediate in the synthesis of diverse organic compounds. Its structure allows for further chemical modifications, enabling the creation of novel molecular architectures for various research applications.
Pharmaceutical Research
This compound is employed in the exploration of new pharmaceutical agents. The isoxazole ring system is a common feature in many biologically active molecules, making this acid a useful starting material for medicinal chemistry programmes.
Heterocyclic Chemistry Building Block
As a representative of the isoxazole class, it is utilised in studies focused on heterocyclic chemistry. Researchers can leverage its reactivity to develop new synthetic methodologies and explore the properties of isoxazole derivatives.
| Molecular weight | 113.07 |
|---|---|
| Empirical formula | C4H3NO3 |
| Assay | 97% |
| Melting point | 144-148 °C(lit.) |
| Protective equipment | Eyeshields, Gloves, type N95 (US), type P1 (EN143) respirator filter |
|---|---|
| Water hazard class (WGK, DE) | 3 |
Hazard information is provided for guidance. Always consult the product Safety Data Sheet (SDS), available on request, before handling.
Documentation
Every batch ships with a Certificate of Analysis covering assay, identity and purity; the grade is confirmed against your enquiry. Safety Data Sheets and technical data sheets are available on request.
Supply & logistics
Samples for technical evaluation; bulk MOQ by grade and packaging. In-stock material ships in 7–10 working days, worldwide, with full export documentation.
What is Isoxazole-5-carboxylic acid used for?
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Isoxazole-5-carboxylic acid is primarily used as a building block in organic synthesis and pharmaceutical research, facilitating the construction of complex molecules containing the isoxazole heterocyclic system.
What are the CAS number and formula for Isoxazole-5-carboxylic acid?
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The CAS number is 21169-71-1, and the molecular formula is C4H3NO3.
What grade and purity does Tech Serve Solutions supply?
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Tech Serve Solutions supplies Isoxazole-5-carboxylic acid with an assay of 97%. We do not represent this product as USP, BP, or EP grade; it is suitable for research and chemical synthesis purposes.
How should Isoxazole-5-carboxylic acid be handled?
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When handling Isoxazole-5-carboxylic acid, it is essential to use appropriate personal protective equipment, including eyeshields and gloves. A type N95 (US) or type P1 (EN143) respirator filter should be used if airborne exposure is possible.
Is Isoxazole-5-carboxylic acid a controlled substance?
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Based on the provided data, there is no indication that Isoxazole-5-carboxylic acid is a controlled substance.
How is Isoxazole-5-carboxylic acid packed and shipped?
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Tech Serve Solutions adheres to strict packaging and shipping protocols for all its chemical products, ensuring safe and compliant export globally.
How can I request a sample or quote for Isoxazole-5-carboxylic acid?
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To request a sample or a quote, please contact our sales department through the website or by phone, providing the product name and CAS number.
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