Flumequine
[CAS# 42835-25-6]

Identification

• Classification: API >> Synthetic anti-infective drugs >> Nitrofuran
• Name: Flumequine
• Synonyms: 9-Fluoro-6,7-dihydro-5-methyl-1-oxo-1H,5H-benzo[ij]quinolizine-2-carboxylic acid
• Molecular Formula: C₁₄H₁₂FNO₃
• Molecular Weight: 261.25
• CAS Registry Number: 42835-25-6
• EC Number: 255-962-6
• SMILES: CC1CCC2=C3N1C=C(C(=O)C3=CC(=C2)F)C(=O)O

Properties

• Solubility: 3 mg/mL (DMSO) (Expl.)
• Density: 1.5±0.1 g/cm³, Calc.^*
• Index of Refraction: 1.646, Calc.^*
• Boiling Point: 439.7±45.0 °C (760 mmHg), Calc.^*
• Flash Point: 219.7±28.7 °C, Calc.^*

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS07;GHS08 Danger
• Risk Statements: H315-H317-H334
• Safety Statements: P233-P260-P261-P264-P271-P272-P280-P284-P302+P352-P304+P340-P321-P332+P317-P333+P317-P342+P316-P362+P364-P403-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Respiratory sensitization	Resp. Sens.	1	H334
Skin sensitization	Skin Sens.	1	H317
Skin irritation	Skin Irrit.	2	H315
Acute toxicity	Acute Tox.	4	H302
Specific target organ toxicity - repeated exposure	STOT RE	2	H373
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411

Discovery and Applications

Flumequine is a synthetic antibacterial agent belonging to the quinolone class of antibiotics. It was first developed in the 1970s as a fluoroquinolone derivative specifically designed for veterinary use. Its structure is based on a quinolone nucleus with a fluorine atom at the C-6 position, which enhances its antibacterial activity. Flumequine was initially studied for its effectiveness against Gram-negative bacteria, particularly those responsible for infections in animals, including livestock and aquaculture species.

The primary application of flumequine is in veterinary medicine, where it is used to treat bacterial infections in poultry, cattle, and fish. It is particularly effective against pathogens such as Escherichia coli, Salmonella spp., and Aeromonas spp. The mechanism of action involves inhibition of bacterial DNA gyrase, an essential enzyme for DNA replication, transcription, and repair. This leads to the disruption of bacterial cell division and ultimately cell death. Due to its broad-spectrum activity and oral bioavailability, flumequine has been widely adopted for prophylactic and therapeutic purposes in animal husbandry.

Despite its effectiveness, the use of flumequine has been subject to regulatory scrutiny due to concerns over antibiotic resistance and residues in food products. Many countries have restricted its use in food-producing animals to prevent the development of resistant bacterial strains. Research continues into alternative quinolone derivatives with improved efficacy and safety profiles, as well as strategies to mitigate antimicrobial resistance.

Flumequine remains an important compound in veterinary pharmacology, serving as a reference molecule for the development of new quinolone-based antibiotics. Ongoing studies aim to optimize its pharmacokinetics and investigate its potential for combination therapies to enhance antibacterial efficacy while minimizing resistance risks.

References

1978. In vitro activity of flumequine against Escherichia coli urinary isolates. Antimicrobial Agents and Chemotherapy, 13(6).
DOI: 10.1128/aac.13.6.966

2024. Occurrence, spatiotemporal distribution, and health risk of antibiotics in the Wuhan section of the Yangtze River, China. Environmental Science and Pollution Research, 31(46).
DOI: 10.1007/s11356-024-35513-x