Temafloxacin is a synthetic fluoroquinolone antibacterial API belonging to the quinolone class of antimicrobial compounds. It was developed as an orally active antibacterial agent and marketed historically under the brand name Omniflox. Temafloxacin was approved in the United States in 1992 but was subsequently withdrawn from the U.S. market because of serious adverse reactions. It is therefore important to present Temafloxacin as a pharmaceutical and research API with its historical regulatory status clearly identified rather than as a currently marketed U.S. antibiotic.
Temafloxacin has the molecular formula C21H18F3N3O3 and molecular weight 417.4 g/mol. PubChem identifies 108319-06-8 as the CAS number for the parent compound and 105784-61-0 as the CAS number for Temafloxacin Hydrochloride.
Temafloxacin is a chemically defined fluoroquinolone containing a quinolone carboxylic-acid core, fluorine substituents and a 3-methylpiperazinyl group. The pharmaceutical hydrochloride form is also documented as Temafloxacin Hydrochloride, with molecular formula C21H19ClF3N3O3 and molecular weight 453.8 g/mol.
For API identification, it is important to distinguish the free compound from its hydrochloride salt. The parent Temafloxacin is registered under CAS 108319-06-8, while Temafloxacin Hydrochloride is registered under CAS 105784-61-0.
Temafloxacin is chemically named 1-(2,4-difluorophenyl)-6-fluoro-7-(3-methylpiperazin-1-yl)-4-oxoquinoline-3-carboxylic acid. It contains three fluorine atoms, three nitrogen atoms and three oxygen atoms within its molecular structure. PubChem reports an exact mass of 417.13002593 Da and a topological polar surface area of 72.9 Ų for the parent compound.
The molecule belongs to the fluoroquinolone antibacterial class and acts primarily through inhibition of bacterial DNA replication enzymes.
Temafloxacin, like other fluoroquinolone antibacterials, interferes with bacterial DNA synthesis by inhibiting DNA gyrase and topoisomerase IV. These enzymes are required for DNA replication, transcription and chromosome segregation.
Inhibition of these bacterial enzymes produces DNA damage and ultimately results in bacterial cell death. Temafloxacin demonstrated activity against a range of Gram-positive and Gram-negative organisms during its development.
Temafloxacin has historically been investigated and used for systemic bacterial infections, including respiratory, urinary and skin infections. PubChem records its historical therapeutic use for lower respiratory tract infections, genital and urinary infections and skin infections.
However, because of its historical withdrawal from the U.S. market, modern product descriptions should avoid implying that Temafloxacin is a currently approved U.S. therapeutic product.
Potential pharmaceutical/API applications include:
Temafloxacin is a small-molecule API suitable for conventional pharmaceutical analytical characterization. Appropriate testing can include identity by spectroscopic and chromatographic methods, assay by HPLC, related substances, residual solvents, water or moisture, inorganic residues and other applicable quality attributes.
Published chemical-reference data describe Temafloxacin as a white to off-white solid and report that it can be slightly soluble in aqueous acid, DMSO and methanol.
A published physicochemical study of quinolones reported Temafloxacin's intrinsic-solubility and melting-point characteristics under controlled experimental conditions. The reported melting-point data vary depending on the solid form and experimental treatment, so a single literature melting point should not automatically be used as a pharmaceutical release specification.
Temafloxacin API manufacturing involves controlled chemical synthesis followed by purification, isolation and characterization. The manufacturing process should control starting materials, reaction-related impurities, residual solvents, stereochemical/structural identity and final product purity.
Because Temafloxacin is an older fluoroquinolone API without a currently established universal public release specification covering all of the CMS fields, commercial specifications should be based on the intended regulatory market and the manufacturer's validated analytical methods.
Temafloxacin is reported as slightly soluble in aqueous acid, DMSO and methanol.
A published experimental study reported an intrinsic-solubility value of approximately 1.58 × 10⁻⁴ M at 25°C for Temafloxacin under the study conditions. This corresponds to approximately 0.066 g/L (0.066 mg/mL) based on its molecular weight, but this is an experimental physicochemical value and not a pharmaceutical API release specification.
Temafloxacin API should be packaged in suitable pharmaceutical-grade, well-closed containers that protect the material from moisture, contamination and unsuitable environmental exposure.
Commercial chemical references recommend 2–8°C with protection from light for certain Temafloxacin material grades. Because these conditions can differ according to material grade and stability data, pharmaceutical API storage should follow the validated manufacturer's stability program.
Pharmaceutical-grade Temafloxacin API documentation may include:
Temafloxacin is a structurally complex fluoroquinolone requiring appropriate control of chemical identity, assay, related substances, residual solvents, moisture and physical characteristics. A quality-focused manufacturing program should employ validated HPLC, spectroscopic and other suitable analytical procedures.
Because Temafloxacin was withdrawn from the U.S. market due to serious adverse reactions, regulatory status and intended market should be carefully considered when developing or supplying Temafloxacin API.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |