Sulfapyridine is a sulfonamide antibacterial active pharmaceutical ingredient (API) belonging to the sulfonamide class of antimicrobial compounds. It is chemically identified as 4-amino-N-pyridin-2-ylbenzenesulfonamide and has CAS Number 144-83-2, molecular formula C₁₁H₁₁N₃O₂S and molecular weight 249.29 g/mol.
Sulfapyridine is an established sulfonamide compound that has been used in pharmaceutical applications and is also recognized as a metabolite associated with sulfasalazine. NIST identifies Sulfapyridine as 2-sulfanilamidopyridine and related chemical names.
Sulfapyridine contains a sulfanilamide group attached to a pyridine ring. Its chemical structure provides the characteristic functionality associated with sulfonamide antibacterial compounds.
The API is generally obtained as a crystalline solid and can be characterized using infrared spectroscopy, chromatographic techniques and other appropriate analytical procedures.
Sulfapyridine has a molecular weight of 249.29 g/mol and CAS Number 144-83-2.
Sulfapyridine is associated with sulfonamide antibacterial applications. Its antimicrobial action is based on interference with bacterial folate synthesis.
As a structural analogue of para-aminobenzoic acid (PABA), sulfapyridine can competitively inhibit dihydropteroate synthase, interfering with the production of folate intermediates required for bacterial growth.
Sulfapyridine is also formed as a metabolite of sulfasalazine and has pharmaceutical relevance in products where sulfasalazine metabolism is involved.
Sulfapyridine API can be evaluated using identity, assay, moisture, inorganic-residue and physical-property testing appropriate to the applicable specification.
The USP monograph defines Sulfapyridine as containing 99.0–100.5% Sulfapyridine calculated on the dried basis.
Typical analytical controls may include:
A current analytical specification reports HPLC ≥94%, loss on drying ≤0.5%, sulfated ash ≤0.1% and melting point 190–193°C for its specified grade.
Swapnroop Drugs and Pharmaceuticals provides pharmaceutical API manufacturing capabilities for Sulfapyridine with quality-focused analytical evaluation and documentation.
Sulfapyridine API can be handled according to applicable pharmacopoeial requirements and agreed customer specifications. Quality evaluation can address identity, assay, moisture, inorganic residue, related substances and physical characteristics.
For pharmaceutical companies requiring Sulfapyridine API from an India-based manufacturer, specification alignment, analytical testing, batch consistency and appropriate documentation are important considerations.
Sulfapyridine API should be stored in suitable, tightly closed pharmaceutical packaging to protect the material from contamination, moisture and excessive environmental exposure.
Recommended handling includes:
A pharmaceutical secondary standard recommends storage at 2–30°C, while a commercial analytical product recommends a cool, dark environment below 15°C. For commercial API storage, the approved product specification should take precedence.
Depending on customer and regulatory requirements, documentation may include:
Swapnroop Drugs and Pharmaceuticals focuses on pharmaceutical API manufacturing with quality systems, analytical evaluation and documentation intended to support pharmaceutical applications.
Sulfapyridine API is handled according to defined quality requirements with attention to identity, assay, impurities, physical characteristics and batch-to-batch consistency.
Customers can discuss Sulfapyridine API requirements, applicable specifications, packaging and documentation with Swapnroop Drugs and Pharmaceuticals.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 99.0–100.5% |
| Loss on Drying | NMT 0.5% |
| Residue on Ignition | NMT 0.1% |
| Melting Point | 190–193°C |