Josamycin – Properties, Uses, and Bioactivity
Properties:
Melting point: 131.5?°C
Specific rotation: D25 -70° (c = 1 in ethanol)
Boiling point: 763.27?°C (approximate)
Density: 1.1547?g/cm3 (approximate)
Refractive index: 1.6220 (estimated)
Storage conditions: Inert atmosphere, store in freezer under -20?°C
Solubility: Soluble in ethanol
Physical form: Powder
Acidity (pKa): 7.1 (40% aqueous methanol)
Color: White to slightly yellow
Merck: 13,5286
Stability: Hygroscopic
InChIKey: XJSFLOJWULLJQS-NGVXBBESSA-N
Pharmacological Action:
Josamycin has antibacterial activity similar to erythromycin. It is effective against:
Gram-positive bacteria: Staphylococcus aureus, hemolytic Streptococcus, Streptococcus pneumoniae, Corynebacterium diphtheriae, Clostridium tetani, Bacillus anthracis, etc.
Some Gram-negative bacteria: Neisseria gonorrhoeae, Bordetella pertussis, Brucella species.
Other pathogens: Mycoplasma, Chlamydia, Rickettsia, Spirochetes.
Sensitive to Campylobacter and Legionella species.
More effective than erythromycin against Gram-positive anaerobes.
Indications:
Clinically used for infections caused by sensitive bacteria, including:
Respiratory tract infections
Biliary tract infections
Suppurative skin infections
Otitis media, sinusitis, tonsillitis, periodontal abscesses
Also effective against staphylococcal infections resistant to penicillin and erythromycin.
Assay Method:
The bioassay for josamycin potency mainly uses the tube-disk method. This method relies on the diffusion of antibiotics in agar containing sensitive bacteria. Zones of inhibition form proportional to the concentration of the antibiotic. It reflects the actual clinical effectiveness and is internationally recognized.
Bioactivity:
Josamycin (also known as EN-141, Kitasamycin A3, Leucomycin A3, Turimycin A5) is a macrolide antibiotic derived from Streptomyces narbonensis. It exhibits broad antibacterial activity against a wide range of pathogens.
Target Kd: 5.5?nM (ribosome)
Josamycin is a macrolide with strong activity against both common and resistant bacterial pathogens, making it valuable for clinical and therapeutic use.