Erythromycin is a macrolide antibiotic that acts on the 50S subunit of the ribosome of bacterial cells to inhibit bacterial protein synthesis. Cyclic ester erythromycin is a semi-synthetic derivative of erythromycin. The introduction of the cyclic carbonate group greatly improves the esterophilicity of erythromycin, thereby increasing its absorbability. Experimentally, this structural change can reduce the serum protein binding rate, improve antibacterial activity and reduce toxicity. It is suitable for pneumonia caused by Mycoplasma pneumoniae, Legionella pneumophila, Chlamydia pneumoniae, skin soft tissue infections, non-gonorrheal vaginitis, gonorrhea, as well as enteritis caused by Campylobacter spp. and gastritis caused by Pylori spp. and whooping cough disease in children when no effective topical treatment options are available or when other antibiotics cannot be used.