Catalyst Promoted Synthesis, Computational and Enzyme Inhibition Studies of Coumarin Esters

In the present study, a new series of ester analogues of substituted coumarin-3-carboxylic acids were synthesized which were typically accessed via a facile esterification reaction between propargyl alcohol and appropriately substituted coumarin-3-carboxylic acids (1-5). This new environmentally benign solid acid catalyst catalyzed, synthetic eco-friendly approach resulted in a noteworthy progress in synthetic efficiency (89-94 % yield), high purity, operational simplicity, mild reaction conditions, cleaner reaction profiles, recyclability of the catalyst and minimizing the production of chemical wastes without using highly toxic reagents for the synthesis. The molecular structure of compound 6 was authenticated by single crystal X-ray crystallographic analysis. The structure and morphology of the catalyst has been established on the basis of FT-IR, scanning electron microscopy-energy dispersion X-ray spectrometry and transmission electron microscopy. The promising bioactive score against enzymatic inhibition prompted us to carry out acetylcholinesterase inhibition screening of the synthesized compounds (6-10). A computer-aided molecular docking study was carried out to validate the specific binding mode of the newly synthesized compounds into the active site of receptor to bear out the specific binding modes of the compounds.