Understanding the Stereoselective Mechanism of Diniconazole Enantiomers Interacting with Serum Albumins

Interactions of chiral pharmaceuticals and serum albumins show enantioselectivity. Herein, UV-Vis absorption spectroscopy, fluorescent spectroscopy, and molecular docking technology were applied in investigation of enantioselective interactions between diniconazole enantiomers and bovine/human serum albumins (BSA/HSA). The results showed that serum albumins possessed stronger binding affinity for R-diniconazole than S-diniconazole; fluorescent quenching of serum albumins induced by diniconazole enantiomers was ascribed to static quenching mechanism; the docking energies between R-diniconazole and S-diniconazole with HSA were -26.4 kJ/mol and -23.6 kJ/mol, and the docking energies with BSA were -27.6 kJ/mol and -23.3 kJ/mol, respectively, which indicates that binding of serum albumin with R-diniconazole was more stable than that with S-enantiomer. Therefore, this study would provide useful information for the stereoselective mechanism of diniconazole in biological system.