Dirithromycin is a macrolide antibiotic. It used in the treatment of mild to moderate upper and lower respiratory tract infections due to Moraxella catarrhalis, Streptococcus pneumoniae, Legionella pneumophila, H. influenzae, or S. pyogenes, ie, acute exacerbation of chronic bronchitis, secondary bacterial infection of acute bronchitis, community-acquired pneumonia, pharyngitis/tonsillitis, and uncomplicated infections of the skin and skin structure due to Staphylococcus aureus.
Dirithromycin is a more lipid-soluble prodrug derivative of 9S-erythromycyclamine prepared by condensation of the latter with 2-(2-methoxyethoxy)acetaldehyde. The 9N, 11O-oxazine ring thus formed is a hemi-aminal that is unstable under both acidic and alkaline aqueous conditions and undergoes spontaneous hydrolysis to form erythromycyclamine. Erythromycyclamine is a semisynthetic derivative of erythromycin in which the 9-ketogroup of the erythronolide ring has been converted to an amino group.
Dirithromycin brand name is Dynabac.