Saturation transfer difference NMR spectroscopy was employed to characterize epitopes of macrolide antibiotics, azithromycin, oleandomycin and telithromycin binding to bovine serum albumin. The structural parts of azithromycin and oleandomycin in intimate contact with bovine serum albumin were found to be similar while those of telithromycin showed similarities but also some differences. The latter were mostly due to different structural elements of antibiotics that interact with the protein, especially the alkyl-heteroaryl side chain in telithromycin and cladinose and desosamine sugars in azithromycin and oleandomycin. The epitope maps as
determined in this study can contribute to better understanding of the overall bioactivity of macrolides
