Investigation of binding mode of novel 2,4-diketo esters to BSA

Abstract

2,4-Diketo esters are well-known for their wide pharmacological activities as well as their usage in a lot of synthetic transformations. The specific structure of 2,4-diketo esters with many carbonyl groups and the presence of keto-enol tautomerism give suitable chemical properties for many applications. Therefore, an affinity for one of the binding sites of bovine serum albumin (BSA) of 2,4-diketo esters possessing good antimicrobial activity, was examined. Binding modes of compounds A and B were determined using fluorescence spectroscopy. Eosin Y was used as a marker for Sudlow’s Site I (subdomain IIA), while ibuprofen was used as a marker for Sudlow’s Site II (subdomain IIIA). Obtained values of Ka suggested that both compounds reversibly bind to BSA. Due to the values of Ka in the presence of site markers, the site II is more likely to be occupied by compound A, and compound B uses other binding modes. The presented results will help to improve the research of the mechanism of the interaction between transport proteins and similar compounds.