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Updated: May 25, 2026

Visualization of Bacterial Resistance using Fluorescent Antibiotic Probes
Published on: March 2, 2020
Structure-activity relationships of novel alkylides: 3-O-arylalkyl clarithromycin derivatives with improved
Jian-Hua Liang1, Xiao-Li Li, He Wang
1School of Life Science, Beijing Institute of Technology, Beijing, China. ljhbit@bit.edu.cn
Abstract:
A series of novel alkylides, possessing 3-O-arylalkyl group instead of 3-O-cladinose, were designed, synthesized and evaluated for in vitro antibacterial activities. The increased potency clearly ranked by the order of 3-O-(3-aryl-2-propargyl), 3-O-(3-aryl-E-prop-2-enyl), 3-O-(3-aryl-propyl), and 3-O-(3-aryl-Z-prop-1-enyl) groups. Some alkylides, exemplified by 7a, 10a, 21, 22, 26, 27 and 33, showed improved activities against inducible MLS(B) resistance and efflux resistance compared to the second-generation macrolides. Among them, 26 possessed comparable activities against erythromycin-susceptible Staphylococcus aureus, Streptococcus pneumoniae and Streptococcus pyogenes (MICs of 0.016-0.5 μg/mL). Moreover, 26 displayed dramatically enhanced potency against both efflux resistant and inducibly MLS(B) resistant strains (MICs of 0.125-0.5 μg/mL) resistant to clarithromycin and azithromycin (MICs of 1- >254 μg/mL), independent of methicillin-susceptible and methicillin-resistant phenotypes.
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