The primary target of Sulfalene is dihydropteroate synthase (DHPS), a key enzyme in the bacterial folate synthesis pathway. It acts as a competitive inhibitor, competing with para-aminobenzoic acid (PABA), the natural substrate of the enzyme. By inhibiting DHPS, Sulfalene prevents the synthesis of dihydrofolate, a precursor of tetrahydrofolate, which is essential for bacterial DNA synthesis and cell replication. This mechanism of action is characteristic of the sulfonamide class of antibiotics.

In vitro, Sulfalene is a competitive inhibitor of dihydropteroate synthase (DHPS). It exhibits antimicrobial activity against various bacterial pathogens. Its activity is assessed by determining the minimum inhibitory concentration (MIC) against susceptible bacterial strains. The compound's long-acting nature is attributed to its high plasma protein binding. Sulfalene has been extensively studied in scientific research for its antimicrobial activity.

In vivo, Sulfalene is used for the treatment of chronic bronchitis, urinary tract infections, and malaria. It is a long-acting sulfonamide, allowing for less frequent dosing compared to short-acting sulfonamides. The compound is effective against various bacterial infections and has been used in the formulation of drugs targeting specific diseases. Its long-acting plasma-bound nature contributes to its sustained antimicrobial activity.

The in vitro activity of Sulfalene is assessed using standard susceptibility testing methods. Minimum inhibitory concentrations (MICs) against various bacterial strains are determined using broth microdilution or agar dilution methods. Serial two-fold dilutions of the compound are prepared in appropriate growth medium (e.g., Mueller-Hinton broth). A standardized bacterial inoculum is added to each well, and the plates are incubated at 35-37°C for 18-24 hours. The MIC is determined as the lowest concentration that inhibits visible growth. For mechanistic studies, the inhibition of dihydropteroate synthase can be assessed using cell-free enzyme assays.

For cellular assays, bacterial cultures of susceptible strains are grown in appropriate media. Cells are treated with various concentrations of Sulfalene (typically 0.1-100 µg/mL) for defined periods. Bacterial viability is assessed by colony counting or by measuring optical density at 600 nm. The effect on folate synthesis can be evaluated by measuring the levels of folate metabolites in bacterial cells using HPLC or LC-MS/MS. Time-kill curves are generated by sampling at multiple time points to determine the bactericidal kinetics.

In vivo, Sulfalene is typically administered orally to patients or animal models. For the treatment of urinary tract infections or respiratory infections, the compound is administered at recommended doses. Efficacy is assessed by measuring the reduction in bacterial burden in urine, sputum, or tissue samples. In animal models of infection, the compound is administered, and survival or bacterial clearance is assessed.

Specific pharmacokinetic data for Sulfalene is not detailed in the provided search results. It is a long-acting plasma-bound sulfonamide with high protein binding. The compound is absorbed after oral administration and distributed throughout the body. It is metabolized in the liver and excreted in urine. Its long half-life allows for once-daily or less frequent dosing.

The primary toxicity of Sulfalene is related to its sulfonamide class effects. Common side effects include gastrointestinal disturbances, hypersensitivity reactions (rash, fever), and hematological effects (e.g., agranulocytosis, hemolytic anemia). The compound should be used with caution in patients with sulfonamide allergy, renal impairment, or hepatic impairment. Long-term use may cause crystalluria, which can be prevented by adequate hydration. The compound is contraindicated in patients with porphyria.

Sulfamethopyrazine belongs to the pyrazine class of compounds and is a sulfonamide antibiotic. It is a long-acting plasma-bound sulfonamide used to treat respiratory tract infections, urinary tract infections, and malaria. Sulfamethopyrazine is a long-acting sulfonamide antibiotic used to treat chronic bronchitis, urinary tract infections, and malaria. It is a long-acting plasma-bound sulfonamide used to treat respiratory tract infections, urinary tract infections, and malaria. Indications: Used to treat urinary tract infections and chronic bronchitis. Mechanism of Action: Sulfamethopyrazine is a competitive inhibitor of bacterial dihydropteranoic acid synthase. It prevents the binding of this enzyme's substrate, para-aminobenzoic acid (PABA). In these organisms, this inhibited reaction is essential for folic acid synthesis. Pharmacodynamics: Sulfamethopyrazine is a sulfonamide antibiotic. Sulfonamides are synthetic antibacterial antibiotics with broad-spectrum antibacterial activity against most Gram-positive bacteria and many Gram-negative bacteria. However, many strains of the same species may develop resistance. Sulfonamides inhibit bacterial growth by competitively inhibiting para-aminobenzoic acid in the folate metabolic cycle. Bacteria have similar sensitivity to various sulfonamides; resistance to one sulfonamide means resistance to all sulfonamides. Most sulfonamides are well absorbed orally. However, parenteral administration is difficult because soluble sulfonamide salts are strongly alkaline and irritating to tissues. Sulfonamides are widely distributed in all tissues. High concentrations are found in pleural effusions, ascites, synovial fluid, and intraocular fluid. Although these drugs are no longer used to treat meningitis, high concentrations remain in cerebrospinal fluid during meningeal infections. Pus can inhibit their antibacterial activity.
Sulfalene is a long-acting sulfonamide antibiotic used for the treatment of chronic bronchitis, urinary tract infections, and malaria. It is a competitive inhibitor of dihydropteroate synthase and belongs to the sulfonamide class of antibiotics. Its long-acting nature, due to high plasma protein binding, allows for less frequent dosing. Sulfalene is not widely used in many countries due to the availability of more effective and safer antibiotics, but it remains an important therapeutic option in some regions. It is available from chemical suppliers for research purposes.

C11H12N4O3S

280.3

280.063

152-47-6

Sulfalene-13C6

9047

White to off-white solid powder

1.5±0.1 g/cm3

488.6±55.0 °C at 760 mmHg

270 °C (dec.)(lit.)

249.3±31.5 °C

0.0±1.2 mmHg at 25°C

1.647

1.1

2

7

4

19

376

0

S(C1C([H])=C([H])C(=C([H])C=1[H])N([H])[H])(N([H])C1C(=NC([H])=C([H])N=1)OC([H])([H])[H])(=O)=O

KXRZBTAEDBELFD-UHFFFAOYSA-N

InChI=1S/C11H12N4O3S/c1-18-11-10(13-6-7-14-11)15-19(16,17)9-4-2-8(12)3-5-9/h2-7H,12H2,1H3,(H,13,15)

4-amino-N-(3-methoxypyrazin-2-yl)benzenesulfonamide

Sulfaleno; Sulfalene; Sulfalen

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 : ~100 mg/mL (~356.76 mM)

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.)