Quinolone
It is referred to as a 1-difluorophenyl-6-fluoroquinolone antibacterial agent. [1]

Temafloxacin (0-64 µg/mL; 18–24 h) exhibits good antibacterial activity against gram-positive and gram-negative bacteria, with MIC ranges for E. Coli, P. aeruginosa, and S. aureus, respectively, of <0.004-0.5, 0.5-2, and 0.06-0.25 µg/mL[1].

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Temafloxacin hydrochloride exhibits broad-spectrum in vitro antibacterial activity. Against 16 strains of Escherichia coli, the MIC range was ≤0.004–0.5 µg/ml, with MIC50 and MIC90 values of 0.06 µg/ml [1]
Against 13 strains of Pseudomonas aeruginosa, the MIC range was 0.5–2 µg/ml, with MIC50 and MIC90 values of 1 µg/ml [1]
Against 17 strains of Staphylococcus aureus, the MIC range was 0.06–0.25 µg/ml, with MIC50 and MIC90 values of 0.125 µg/ml, showing activity equivalent to difloxacin and ciprofloxacin [1]
Against streptococci (Streptococcus pyogenes and Streptococcus pneumoniae), Temafloxacin was as active as ciprofloxacin and 2 two-fold dilutions (approximately 4-fold) more active than difloxacin [1]
Its activity was equal to or greater than that of difloxacin and ciprofloxacin against Campylobacter species, Neisseria gonorrhoeae, and Legionella pneumophila [1]
Against anaerobic bacteria, including Bacteroides fragilis, Temafloxacin was as active as difloxacin and ciprofloxacin [1]
The antibacterial activity of Temafloxacin was not significantly affected by changes in pH (6.5, 7.2, 8.0) when tested against E. coli, P. aeruginosa, and S. aureus [1]
The presence of 50% human serum increased the MICs of Temafloxacin by 1 to 3 two-fold dilutions against the test strains [1]
In human urine adjusted to pH 6.5, the MICs of Temafloxacin increased by 2 to 5 two-fold dilutions [1]
Time-kill studies against E. coli Juhl showed that Temafloxacin at 4x and 8x MIC reduced viable counts by >99% within 2 hours and >99.9% within 4 hours [1]
The frequency of spontaneous resistance development to 8x MIC of Temafloxacin was < 10^-9 for S. aureus, E. coli, and P. aeruginosa [1]

Temafloxacin (6.25, 25, 100 mg/kg; p.o. ; single dose) exhibits good anti-mouse pyelonephritis activity[1].
With the exception of the central nervous system (CNS), temafloxacin hydrochloride (100 mg/kg; p.o. or s.c.; single) exhibits rapid gastrointestinal absorption and excellent tissue and body fluid penetration and concentration[1].

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In mouse systemic protection tests (oral administration), Temafloxacin showed ED50 values of 2.2 mg/kg/day and 4.7 mg/kg/day against two different Staphylococcus aureus infections, making it as active as difloxacin and 5 to 10 times more active than ciprofloxacin [1]
Against Streptococcus pyogenes infection (oral), Temafloxacin had an ED50 of 11.1 mg/kg/day, as active as difloxacin and more active than ciprofloxacin (ED50 >100 mg/kg/day) [1]
Against gram-negative enteric bacteria (E. coli, Proteus mirabilis, Providencia stuartii) and P. aeruginosa infections, Temafloxacin administered orally was generally as active as difloxacin and ciprofloxacin [1]
Against Salmonella typhimurium infection, Temafloxacin (oral ED50 18.2 mg/kg/day) was three times less active than difloxacin but five times more active than ciprofloxacin [1]
In neutropenic mice infected with P. aeruginosa, orally administered Temafloxacin showed an ED50 of 32.9 mg/kg/day, similar to difloxacin and ciprofloxacin [1]
In a murine pyelonephritis model, oral administration of Temafloxacin (6.25 to 100 mg/kg/day) was as effective as difloxacin and ciprofloxacin in reducing bacterial counts in kidneys infected with P. aeruginosa or Proteus mirabilis [1]

Cell Line: E. coli (16 strains), P. aeruginosa (13 strains), and S. aureus (17 strains).
Concentration: 0-64 µg/mL
Incubation Time: 18-24 h
Result: MIC ranges of <0.004-0.5 (MIC 90%=0.06, =0.06), 0.5-2 (MIC 90%=1, MIC 50%=1), and 0.06-0.25 µg/mL (MIC 90%=0.125, MIC 50%=0.125) inhibited 16 strains of E. coli, P. aeruginosa, and S. aureus. 90% and 50% of the isolates are included in the MIC (unit: µg/mL).

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MICs were determined by the agar dilution method according to National Committee for Clinical Laboratory Standards guidelines, using an inoculum of 10^4 CFU per spot. Mueller-Hinton agar (pH 7.3) was used for most bacteria, supplemented with blood or specific factors for fastidious organisms. Plates were incubated at 35°C [1]
Microdilution tests in Mueller-Hinton broth were used to evaluate the effect of pH (adjusted to 6.5, 7.2, or 8.0) on MICs against E. coli, P. aeruginosa, and S. aureus [1]
The effect of serum was tested by adding 50% (vol/vol) inactivated human serum (pH 7.2) to Mueller-Hinton broth and determining MICs via microdilution [1]
The effect of urine was tested using pooled human urine adjusted to pH 6.5, 7.2, or 8.0, and MICs were determined by a microdilution method [1]
For time-kill studies, logarithmic-phase E. coli Juhl culture was added to broth containing Temafloxacin at 4x or 8x MIC. Samples were taken at intervals, serially diluted, and plated on drug-free agar for viable cell counting [1]
The frequency of spontaneous resistance was determined by plating high-density bacterial cultures onto agar containing 4x or 8x MIC of Temafloxacin and counting resistant colonies [1]

Animal Model: Female CF-1 mice (20-25 g) (murine pyelonephritis model)[1].
Dosage: 6.25, 25, 100 mg/kg
Administration: Orally; single.
Result: Reduced the number of viable bacteria in the kidneys of mice.

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For mouse systemic protection tests, female CF-1 mice (20-25 g) were injected intraperitoneally with 0.5 ml of bacterial suspension containing 10 to 1000 LD50s. Temafloxacin hydrochloride (and comparators) were administered subcutaneously or orally at 1 and 5 hours post-infection (except for Salmonella typhimurium infection, where drugs were given at 24 and 28 hours post-infection). The median effective dose (ED50) was calculated based on cumulative mortality on day 6 (day 22 for S. typhimurium) using trimmed logit analysis [1]
For infection in neutropenic mice, mice were made neutropenic by administering cyclophosphamide (150 mg/kg on day 0 and 110 mg/kg on day 4). On day 5, they were infected and medicated as described for protection tests [1]
For the pyelonephritis model, mice were intravenously injected with carrageenan (10 mg/kg). One week later, they were intravenously infected with P. aeruginosa or Proteus mirabilis. Oral treatment with Temafloxacin (and comparators) was given at 18 and 30 hours post-infection. Mice were sacrificed 18 hours after the final dose, and kidneys were homogenized for quantitative culture [1]
For pharmacokinetic studies, female CF-1 mice were administered a single oral or subcutaneous dose of 100 mg/kg of Temafloxacin hydrochloride. Blood and urine samples were collected from groups of five mice at 0.5, 1, 2, 3, 6, and 24 hours after dosing [1]

Absorption, Distribution and Excretion
Studies in healthy volunteers have shown that the average bioavailability of timafloxacin exceeds 90%, with minimal inter-individual variability. Metabolism/Metabolites Metabolized in the liver. Biological Half-Life The half-life in patients with normal renal function is approximately 8 hours. In mice, after a single oral administration of 100 mg/kg timafloxacin, the peak serum concentration (Cmax) was 13.5 µg/ml, the area under the serum curve (AUC) was 57.4 µg·h/ml, and the serum half-life (t1/2) was 1.3 hours. The urine recovery rate was 9.1% of the administered dose[1]. After a single subcutaneous injection of 100 mg/kg into mice, the Cmax was 25.2 µg/ml, the AUC was 86.6 µg·h/ml, the t1/2 was 3.4 hours, and the urine recovery rate was 25.3%[1]. The peak serum concentration of temafloxacin in mice after oral administration was about 6 times that of ciprofloxacin and about 2/3 that of desflufloxacin[1]. The AUC of oral temafloxacin was significantly higher than that of ciprofloxacin (57.4 vs. 3.4 µg·h/ml), but lower than that of desflufloxacin (152.5 µg·h/ml)[1].

[1]. Comparative antibacterial activities of temafloxacin hydrochloride (A-62254) and two reference fluoroquinolones. Antimicrob Agents Chemother. 1987 Nov;31(11):1768-74.

[2]. Pankey GA. Temafloxacin: an overview. Am J Med. 1991 Dec 30;91(6A):166S-172S.

1-(2,4-Difluorophenyl)-6-fluoro-7-(3-methylpiperazin-1-yl)-4-oxo-1,4-dihydroquinoline-3-carboxylic acid is a quinolone compound with the structure 4-oxo-1,4-dihydroquinoline-3-carboxylic acid, in which the 1, 6, and 7 positions are substituted with 2,4-difluorophenyl, fluorine, and 3-methylpiperazin-1-yl, respectively. It is a quinolone compound, and also an amino acid, monocarboxylic acid, organofluorine compound, secondary amine compound, tertiary amine compound, N-arylpiperazine compound, and quinolone antibiotic. Temaxane is an antibiotic belonging to the fluoroquinolone class. It was first approved for marketing in the United States in 1992, but was soon withdrawn due to reports of serious adverse reactions (such as allergic reactions and hemolytic anemia), including three deaths. Indications: Used to treat lower respiratory tract infections, genitourinary tract infections (such as prostatitis), and skin infections. Mechanism of Action The bactericidal effect of timafloxacin stems from its interference with the activity of bacterial DNA gyrase and topoisomerase IV, both essential enzymes 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 the preferred target for Gram-positive bacteria. Interference with these two topoisomerases leads to bacterial chromosome strand breaks, supercoiling, and rejoining. Consequently, DNA replication and transcription are inhibited. Pharmacodynamics Timafloxacin was a fluoroquinolone antibiotic marketed by Abbott Laboratories under the brand name Omniflox, and was withdrawn from the market in 1992 due to fatal adverse reactions. Fluoroquinolones, such as lomefloxacin, have 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 are also effective against Shigella, Salmonella, Campylobacter, Neisseria gonorrhoeae, and multidrug-resistant Pseudomonas and Enterobacter. Temafloxacin hydrochloride is 1-(o,p-difluorophenyl)-6-fluoro-1,4-dihydro-4-oxo-7-(3-methyl-1-piperazinyl)-quinoline-3-carboxylic acid hydrochloride. Compared to desflufloxacin, its chemical modifications include the introduction of an additional fluorine atom at the ortho position of the benzene ring and a methyl group at the 3-position of the piperazine ring, thereby improving its water solubility [1].
Its research and development goal is to improve its activity against Gram-negative bacteria, making it superior to desflufloxacin, and having higher water solubility, as well as a serum half-life shorter than desflufloxacin but longer than ciprofloxacin[1].
Studies have shown that temafloxacin is a broad-spectrum quinolone drug with in vitro activity and pharmacokinetic properties between ciprofloxacin and desflufloxacin. It has better oral in vivo efficacy against certain pathogens, which is attributed to its better oral absorption, higher serum concentration and larger AUC[1].

C21H18F3N3O3

417.39

417.13

C, 60.43; H, 4.35; F, 13.66; N, 10.07; O, 11.50

108319-06-8

Temafloxacin hydrochloride;105784-61-0

60021

Solid powder

1.427g/cm3

608.9ºC at 760mmHg

322.1ºC

1.11E-15mmHg at 25°C

1.603

3.298

2

9

3

30

721

0

O=C(C1=CN(C2=CC=C(F)C=C2F)C3=C(C=C(F)C(N4CC(C)NCC4)=C3)C1=O)O

QKDHBVNJCZBTMR-UHFFFAOYSA-N

InChI=1S/C21H18F3N3O3/c1-11-9-26(5-4-25-11)19-8-18-13(7-16(19)24)20(28)14(21(29)30)10-27(18)17-3-2-12(22)6-15(17)23/h2-3,6-8,10-11,25H,4-5,9H2,1H3,(H,29,30)

1-(2,4-Difluorophenyl)-6-fluoro-7-(3-methylpiperazin-1-yl)-4-oxoquinoline-3-carboxylic acid

trade name: Omniflox; A-62254; A62254; A 62254

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)

DMSO : < 1 mg/mL

Solubility in Formulation 1: ≥ 0.5 mg/mL (1.20 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 5.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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Solubility in Formulation 2: 10% DMSO+90% Corn Oil: ≥ 0.5 mg/mL (1.20 mM)

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