Shanghai Ruifu Chemical Co., Ltd. is the leading manufacturer of 5-Methylisoxazole-4-Carboxylic Acid (CAS: 42831-50-5) with high quality. Ruifu can provide worldwide delivery, competitive price, excellent service, small and bulk quantities available. Purchase 5-Methylisoxazole-4-Carboxylic Acid, Please contact: alvin@ruifuchem.com
| Chemical Name | 5-Methylisoxazole-4-Carboxylic Acid |
| Synonyms | 5-Methyl-4-Isoxazolecarboxylic Acid |
| Impurity | Leflunomide EP Impurity D/ Leflunomide BP Impurity D |
| Stock Status | In Stock, Commercial Scale |
| CAS Number | 42831-50-5 |
| Molecular Formula | C5H5NO3 |
| Molecular Weight | 127.10 g/mol |
| Melting Point | 145.0 to 149.0℃(lit.) |
| Density | 1.348±0.06 g/cm3 |
| Storage Temp. | Cool & Dry Place (2~8℃) |
| COA & MSDS | Available |
| Brand | Ruifu Chemical |
| Items | Inspection Standards | Results |
| Appearance | White to Pale Yellow Crystalline Powder, Odourless | Complies |
| Melting Point | 145.0 to 149.0℃ | 147.8~148.5℃ |
| Loss on Drying | ≤0.50% | 0.13% |
| Residue on Ignition | ≤0.10% | 0.04% |
| Heavy Metals (Pb) | ≤0.002% | <0.002% |
| 3-Methyl Isomeric Compound | ≤0.20% | <0.20% |
| Purity / Analysis Method | >99.0% (HPLC) | 99.74% |
| Infrared Spectrum | Conforms to Structure | Complies |
| 1 H NMR Spectrum | Conforms to Structure | Complies |
| Conclusion | The product has been tested & complies with the given specifications | |
| Uses | Pharmaceutical Intermediate of Leflunomide (CAS: 75706-12-6) | |
Package: Bottle, Aluminium foil bag, 25kg/Cardboard Drum, or according to customer's requirement.
Storage Condition: Store in a tightly closed container. Store in a cool, dry (2~8℃) and well-ventilated warehouse away from incompatible substances. Protect from light and moisture.
Shipping: Deliver to worldwide by air, by FedEx / DHL Express. Provide fast and reliable delivery.
How to Purchase? Please contact Dr. Alvin Huang: sales@ruifuchem.com or alvin@ruifuchem.com
15 Years Experience? We have more than 15 years of experience in the manufacture and export of a wide range of high quality pharmaceutical intermediates or fine chemicals.
Main Markets? Sell to domestic market, North America, Europe, India, Korea, Japanese, Australia, etc.
Advantages? Superior quality, affordable price, professional services and technical support, fast delivery.
Quality Assurance? Strict quality control system. Professional equipment for analysis include NMR, LC-MS, GC, HPLC, ICP-MS, UV, IR, OR, K.F, ROI, LOD, MP, Clarity, Solubility, Microbial limit test, etc.
Samples? Most products provide free samples for quality evaluation, shipping cost should be paid by customers.
Factory Audit? Factory audit welcome. Please make an appointment in advance.
MOQ? No MOQ. Small order is acceptable.
Delivery Time? If within stock, three days delivery guaranteed.
Transportation? By Express (FedEx, DHL), by Air, by Sea.
Documents? After sales service: COA, MOA, ROS, MSDS, etc. can be provided.
Custom Synthesis? Can provide custom synthesis services to best fit your research needs.
Payment Terms? Proforma invoice will be sent first after confirmation of order, enclosed our bank information. Payment by T/T (Telex Transfer), PayPal, Western Union, etc.
Risk Codes
R36/37/38 - Irritating to eyes, respiratory system and skin.
R37/38 - Irritating to respiratory system and skin.
R36 - Irritating to the eyes
R10 - Flammable
Safety Description
S22 - Do not breathe dust.
S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice.
S36/37/39 - Wear suitable protective clothing, gloves and eye/face protection.
S36 - Wear suitable protective clothing.
S16 - Keep away from sources of ignition.
WGK Germany 3
HS Code 2917399090
Hazard Class IRRITANT
5-Methylisoxazole-4-Carboxylic Acid (CAS: 42831-50-5) is an intermediate for synthesis of Leflunomide (CAS: 75706-12-6). Leflunomide is a kind of isoxazole immunosuppressive drugs with anti-proliferative activity, modern pharmacology classifies this product as antipyretic, analgesic and anti-inflammatory drugs. This product can be rapidly converted to the active metabolites and play a role by the liver and intestinal cytoplasm and microsomes, its; main mechanism is during DNA synthesis, inhibiting a key enzyme-DHODH (DHODH) activity, so that the nucleotides within the B lymphocyte are depleted, it terminates the biosynthesis of DNA and RNA, the cells can not enter s phase, and ultimately can not proliferate, resulting in anti-rheumatic effects, it is suitable for the treatment of adults with active rheumatoid arthritis, ankylosing spondylitis, it can slow bone destruction, alleviate the symptoms and signs. In addition, leflunomide can also inhibit the tyrosine kinase activity, thereby inhibiting proliferation of T cell, B cell and non-immune cells, but it can also, by biosynthesis inhibition of cyclooxygenase-2 (COX2), inhibit prostaglandin synthesis and exert anti-inflammatory effects and inhibit mast cells and basophils histamine release. When this product is used in organ transplant patients, the dose adjustment is difficult, it is mainly used to treat rheumatoid arthritis and other autoimmune diseases.