Chlorquinaldol targets microbial cells through its antimicrobial activity. As a chlorinated 8-hydroxyquinoline derivative, it likely acts by chelating metal ions essential for microbial growth and metabolism, disrupting enzymatic processes and cellular functions. This mechanism is similar to other 8-hydroxyquinoline derivatives, which are known to inhibit bacterial DNA synthesis and disrupt cell membrane integrity. The compound's efficacy against a range of pathogens, including Neisseria gonorrhoeae and Chlamydia trachomatis, has been documented. It exhibits enhanced bactericidal activity in duodenal-pancreatic secretions. Its mechanism of action is primarily antimicrobial, targeting bacterial and fungal pathogens without specific receptor-mediated effects.

In vitro, Chlorquinaldol exhibits antimicrobial activity against a range of pathogens. At concentrations of 0.1-0.2% (w/v), it causes a reduction of Neisseria gonorrhoeae and Chlamydia trachomatis by approximately 10-fold after 60 minutes of exposure. It has enhanced bactericidal activity in duodenal-pancreatic secretions. Its activity is typically assessed by determining the minimum inhibitory concentration (MIC) against various bacterial and fungal strains using standard microbiological methods such as broth microdilution or agar diffusion. The compound's efficacy against dermatophytes and other skin pathogens has been demonstrated in various in vitro studies, supporting its use in topical formulations for skin infections.

In vivo, Chlorquinaldol is used as a topical antiseptic for the treatment of skin infections such as athlete's foot and ringworm. It is also used in combination vaginal tablets with promestriene for the treatment of vaginal infections in European countries. Its topical application allows for localized antimicrobial activity with minimal systemic absorption. The compound's efficacy in clinical settings has been established through its historical use and ongoing applications. However, its use has declined in many regions due to the availability of more modern antimicrobial agents. Comprehensive in vivo pharmacokinetic and pharmacodynamic studies are limited.

In vitro non-cell enzyme/receptor binding assays are not applicable for Chlorquinaldol, as it is an antimicrobial agent that acts through chelation and disruption of microbial metabolism rather than through specific enzyme inhibition. Its antimicrobial activity is assessed through standard microbiological susceptibility tests. The compound's ability to chelate metal ions can be measured using spectrophotometric methods. Its activity against specific pathogens is evaluated using broth microdilution or agar diffusion methods to determine the MIC. These assays are used for quality control and to ensure the compound's effectiveness as an antimicrobial agent.

In vitro cell-based assays for Chlorquinaldol are limited, as it is primarily used as a topical antimicrobial agent. Its cytotoxicity on mammalian cells can be assessed using skin cell lines such as keratinocytes or fibroblasts to evaluate its safety for topical applications. Cells are treated with varying concentrations of the compound, and cell viability is measured using MTT or similar assays. Its antimicrobial activity can be assessed using co-culture models with bacterial or fungal pathogens. However, specific published data on cell-based assays for this compound are limited.

In vivo animal studies for Chlorquinaldol would typically involve topical application to animal models of skin infection to evaluate its efficacy and safety. The compound would be applied to infected skin areas, and parameters such as microbial load, wound healing, and local irritation would be assessed. Standard protocols for skin irritation and sensitization tests would be followed to ensure the compound's safety for topical use. However, specific in vivo studies are not extensively documented in the available literature, as the compound's use is primarily historical and its safety profile is well-established.

Absorption, Distribution and Excretion
The absorption of topically applied chloroquine varies considerably. Reported absorption rates range from 4.2% to 23.5% of the administered dose. This is considerably lower than that of oral formulations, which in the same study achieved an absorption rate as high as 67.6%. Chloroquine is primarily excreted in the urine as sulfate. Approximately 2% is excreted unchanged. Metabolisms/Metabolites 98% of the drug is converted to sulfate and excreted via the kidneys.
Chlorquinaldol has a molecular weight of 228.07 g/mol and a molecular formula of C₁₀H₇Cl₂NO. Its IUPAC name is 5,7-dichloro-2-methylquinolin-8-ol. The compound is also known as Steroxin and Chlorguinaldon. It should be stored as a powder at 2-8°C for up to two years. As a small, lipophilic molecule, it is expected to have good skin penetration when applied topically. Detailed pharmacokinetic parameters such as absorption, distribution, metabolism, and excretion are not extensively documented.

Chlorquinaldol is generally well-tolerated when applied topically, though skin irritation may occur in sensitive individuals. As an 8-hydroxyquinoline derivative, it has a long history of use as a topical antiseptic, and its safety profile is well-established. However, systemic toxicity may occur with excessive use or application to large areas of damaged skin. The compound is not intended for oral or systemic use. Standard safety precautions should be followed when handling the compound in its pure form.

Chloroquinard is a monohydroxyquinoline with the structure quinoline-8-ol, substituted with a methyl group at position 2 and chlorine at positions 5 and 7. It is an antifungal and antibacterial drug, formerly used topically to treat skin conditions and vaginal infections. It possesses antibacterial, antiseptic, and antiprobiotic properties. It is an organochlorine compound and a monohydroxyquinoline. Chloroquinard was previously used under the brand name Sterosan as a topical antiseptic. In the 1950s, it was marketed as a non-iodine alternative and is not associated with sulfonamides or hormones. Currently, chloroquinard is approved by the European Medicines Agency for use in combination with progesterone acetate tablets to treat bacterial vaginosis. Chloroquinard is a standardized chemical allergen. The physiological effects of chloroquinard are achieved through increased histamine release and cell-mediated immunity. It is a topical anti-infective agent used to treat skin, gastrointestinal, and vaginal infections caused by fungi, protozoa, and certain bacteria. In animal studies, it can cause central nervous system damage, therefore parenteral administration is not recommended. It can also be used as a preservative, antibacterial agent, or deodorant. Drug Indications Chloroquinol has historically been used as a topical antiseptic for treating skin infections. In European countries, it is still used in combination with progesterone vaginal tablets to treat vaginal infections. Mechanism of Action The mechanism by which chloroquinol exerts its bactericidal effect is unclear. 8-hydroxyquinoline compounds are known to be bidentate chelators of various metal ions, which are important enzyme cofactors. However, the addition of exogenous metal ions does not appear to alter the minimum inhibitory concentration (MIC) of Mycobacterium tuberculosis, suggesting that its primary mechanism of action is not dependent on chelation. Pharmacodynamics Chloroquinolol has bactericidal activity against both Gram-positive and Gram-negative bacteria. It is more effective against Gram-positive bacteria, particularly Staphylococcus.
Chlorquinaldol is a chlorinated derivative of 8-hydroxyquinoline and an antimicrobial agent used historically as a topical antiseptic for skin infections. It is also known as 5,7-dichloro-2-methylquinolin-8-ol and Steroxin. The compound is used in topical formulations for conditions such as athlete's foot, ringworm, and other skin infections. It maintains use in European countries as a combination vaginal tablet with promestriene. Not a systemic drug; intended for topical use only.

C10H7CL2NO

228.0747

226.99

72-80-0

6301

Light yellow to brown solid powder

1.5±0.1 g/cm3

350.7±37.0 °C at 760 mmHg

108-112 °C (dec.)(lit.)

165.9±26.5 °C

0.0±0.8 mmHg at 25°C

1.679

4.21

1

2

0

14

214

0

ClC1=C([H])C(=C(C2=C1C([H])=C([H])C(C([H])([H])[H])=N2)O[H])Cl

GPTXWRGISTZRIO-UHFFFAOYSA-N

InChI=1S/C10H7Cl2NO/c1-5-2-3-6-7(11)4-8(12)10(14)9(6)13-5/h2-4,14H,1H3

5,7-dichloro-2-methylquinolin-8-ol

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 : ~50 mg/mL (~219.23 mM)

Solubility in Formulation 1: ≥ 2.08 mg/mL (9.12 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (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 20.8 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.08 mg/mL (9.12 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 20.8 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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