Bacterial DNA gyrase and topoisomerase IV. Pefloxacin is a fluoroquinolone antibiotic that inhibits bacterial DNA gyrase and topoisomerase IV. DNA gyrase is an essential enzyme that introduces negative supercoils into DNA, which is critical for DNA replication and transcription. Topoisomerase IV is involved in the decatenation of replicated DNA chromosomes. By inhibiting these enzymes, Pefloxacin blocks DNA replication and transcription, leading to bacterial cell death. Pefloxacin inhibits DNA relaxation catalyzed by topoisomerase I with an IC50 of 45 µg/mL. The compound's broad-spectrum activity is due to its ability to target both gram-negative and gram-positive bacteria. Pefloxacin is a synthetic broad-spectrum fluoroquinolone antibacterial agent.

Pefloxacin demonstrates broad-spectrum antibacterial activity in vitro against most gram-negative and gram-positive bacteria. The compound inhibits DNA relaxation catalyzed by topoisomerase I with an IC50 of 45 µg/mL. Pefloxacin's antibacterial activity is assessed by standard antimicrobial susceptibility testing methods (broth microdilution or agar diffusion). The compound is active against a wide range of bacterial pathogens, including those causing urinary tract infections, respiratory tract infections, and skin infections. Pefloxacin's potency is characterized by its minimum inhibitory concentration (MIC) values against various bacterial strains. The compound is a synthetic broad-spectrum fluoroquinolone antibacterial agent.

Pefloxacin is used clinically for the treatment of a wide range of bacterial infections. It is indicated for the treatment of uncomplicated gonococcal urethritis in males and for gram-negative bacterial infections in the gastrointestinal system and the genitourinary tract. Pefloxacin is also used to treat respiratory tract infections and skin infections. The compound is administered orally or intravenously. Pefloxacin's clinical efficacy has been established through many years of use as an antibiotic. The compound is a well-established antibiotic that has been used clinically for many years.

Antibacterial susceptibility testing is performed using broth microdilution or agar dilution methods according to CLSI guidelines. Bacterial strains (e.g., E. coli ATCC 25922, P. aeruginosa ATCC 27853) are cultured in appropriate media (e.g., Mueller-Hinton broth or agar). Pefloxacin is serially diluted in 96-well plates or agar plates. Bacterial inoculum is added and plates are incubated at 35°C for 16-20 hours. MIC values are determined as the lowest concentration causing complete inhibition of visible growth. Quality control strains are included to ensure assay validity. DNA gyrase and topoisomerase IV inhibition assays are performed using purified enzymes and supercoiled DNA substrates.

Antibacterial activity is evaluated in bacterial cell cultures using standard microbiological methods. Broth microdilution assays are performed in 96-well plates with appropriate media. Bacteria are cultured to logarithmic phase and diluted to a standard inoculum. Pefloxacin is serially diluted and added to wells. Plates are incubated at 35°C for 16-20 hours. MIC values are determined visually or using a microplate reader. Time-kill curve assays are performed to assess bactericidal activity. Each experiment includes quality control strains and antibiotic standards.

In vivo efficacy of Pefloxacin is evaluated in animal models of bacterial infection. Pefloxacin is administered orally or intravenously at doses determined by preclinical studies. Bacterial burden is quantified in infected tissues by CFU plating. Clinical symptoms are monitored. Sample sizes typically range from 6-10 animals per group. Clinical studies have been conducted for urinary tract infections, respiratory tract infections, skin infections, and gonococcal urethritis.

Absorption, Distribution and Excretion
Good oral absorption. Metabolism/Metabolites Metabolized in the liver. Major metabolites are pefloxacin N-oxide and norfloxacin. Biological Half-Life 8.6 hours
Molecular Weight: 333.36. Formula: C17H20FN3O3. CAS No.: 70458-92-3. Appearance: White to off-white crystalline powder. Solubility: DMSO. Storage: Typically at room temperature, protected from light. Pefloxacin is a synthetic broad-spectrum fluoroquinolone antibiotic. Pefloxacin inhibits bacterial DNA gyrase and topoisomerase IV. Pefloxacin is used to treat urinary tract infections, respiratory tract infections, and skin infections.

Protein Binding
20-30%
Pefloxacin is generally well-tolerated at therapeutic doses. Common adverse effects may include gastrointestinal disturbances, headache, dizziness, and photosensitivity. As a fluoroquinolone, it may cause tendinitis and tendon rupture, particularly in older patients. It is contraindicated in patients with quinolone hypersensitivity and in children due to cartilage damage. Pefloxacin is a well-established antibiotic that has been used clinically for many years.

[1].Drlica K, et al. DNA gyrase, topoisomerase IV, and the 4-quinolones. Microbiol Mol Biol Rev. 1997 Sep;61(3):377-92.

[2].Hussy P, et al. Effect of 4-quinolones and novobiocin on calf thymus DNA polymerase alpha primase complex, topoisomerases I and II, and growth of mammalian lymphoblasts. Antimicrob Agents Chemother. 1986 Jun;29(6):1073-8

Pefloxacin is a quinolone antibiotic with the structure 4-oxo-1,4-dihydroquinoline, substituted at positions 1, 3, 6, and 7 with ethyl, carboxyl, fluorine, and 4-methylpiperazin-1-yl groups, respectively. It possesses anti-infective, DNA synthesis inhibitory, and antibacterial activities. It is a quinolone, N-arylPecazine, N-alkylPecazine, quinolone antibiotic, fluoroquinolone antibiotic, and monocarboxylic acid compound. Pefloxacin is a synthetic broad-spectrum fluoroquinolone antibacterial agent effective against most Gram-negative and Gram-positive bacteria. Pefloxacin is a fluoroquinolone antibiotic with broad-spectrum antibacterial activity. Pefloxacin inhibits the activity of microbial DNA gyrase and topoisomerase IV. This interferes with DNA replication and prevents cell division. A synthetic broad-spectrum fluoroquinolone antibacterial agent effective against most Gram-negative and Gram-positive bacteria. Indications Pefloxacin is used to treat uncomplicated gonococcal urethritis in men and Gram-negative bacterial infections of the gastrointestinal and genitourinary tracts. Mechanism of Action Pefloxacin's bactericidal action stems from its interference with the activity of bacterial DNA gyrase and topoisomerase IV, both essential for bacterial DNA transcription and replication. DNA gyrase appears to be the primary target of quinolone drugs against Gram-negative bacteria. Topoisomerase IV appears to be its preferred target against Gram-positive bacteria. Interference with these two topoisomerases leads to bacterial chromosome strand breaks, supercoiling, and rejoining. As a result, DNA replication and transcription are inhibited. Pharmacodynamics Pefloxacin is a fluoroquinolone antibiotic. Fluoroquinolones, including pefloxacin, exhibit excellent antibacterial activity against Gram-negative aerobic bacteria (such as Escherichia coli and Neisseria gonorrhoeae) and Gram-positive bacteria (including Streptococcus pneumoniae and Staphylococcus aureus). They also have effective antibacterial activity against Shigella, Salmonella, Campylobacter, Neisseria gonorrhoeae, as well as multidrug-resistant Pseudomonas and Enterobacteriaceae.
Pefloxacin is also known as 1-ethyl-6-fluoro-7-(4-methylpiperazin-1-yl)-4-oxoquinoline-3-carboxylic acid. Pefloxacin is a synthetic broad-spectrum fluoroquinolone antibiotic. Pefloxacin inhibits bacterial DNA gyrase and topoisomerase IV. Pefloxacin is used to treat urinary tract infections, respiratory tract infections, skin infections, and gonococcal urethritis. Pefloxacin is a well-established antibiotic that has been used clinically for many years. Regulatory approvals exist in many countries.

C17H20FN3O3

333.3634

333.148

70458-92-3

Pefloxacin mesylate;70458-95-6;Pefloxacin-d5;1228182-51-1;Pefloxacin-d3;2733455-58-6;Pefloxacin mesylate dihydrate;149676-40-4

51081

White to off-white solid powder

1.3±0.1 g/cm3

529.1±50.0 °C at 760 mmHg

273.8±30.1 °C

0.0±1.5 mmHg at 25°C

1.594

1.51

1

7

3

24

545

0

O=C(C1=CN(CC)C2=C(C=C(F)C(N3CCN(C)CC3)=C2)C1=O)O

FHFYDNQZQSQIAI-UHFFFAOYSA-N

InChI=1S/C17H20FN3O3/c1-3-20-10-12(17(23)24)16(22)11-8-13(18)15(9-14(11)20)21-6-4-19(2)5-7-21/h8-10H,3-7H2,1-2H3,(H,23,24)

1-ethyl-6-fluoro-7-(4-methylpiperazin-1-yl)-4-oxoquinoline-3-carboxylic acid

1589 RB 1584RB Pefloxacin

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)