Coumarin Analogues as Promising Anti-Obesity Agents: In Silico Design, Synthesis, and In Vitro Pancreatic Lipase Inhibitory Activity

Abstract

A set of coumarin-3-carboxamide analogues were designed, synthesized, and evaluated for their ability to impede pancreatic lipase (PL) activity. Out of all the analogues, 5dh and 5de demonstrated promising inhibitory activity against PL, as indicated by their respective IC₅₀ values of 9.20 and 11.4 μM, as compared to Orlistat (IC₅₀ = 0.97 μM). It was found that analogue 5dh inhibited PL in a competitive manner with an inhibition constant (K_i) of 4.504 μM. Additionally, the docking analysis validated the interactions between the analogue 5dh (MolDock score of −140.251 kcal/mol) and key amino acids in the active site, including Leu 153, Gly 76, Arg 256, His 151, Phe 77, and His 263. The inhibitory activity of these analogues was significantly correlated with their MolDock scores (Pearson's r = 0.6586). Finally, molecular dynamics simulation was also performed for 100 ns in order to elucidate the stability, confirmation and intermolecular interactions of the active analogue 5dh. The results of this investigation suggested that the complex maintained its stability despite the dynamic conditions exhibiting interactions with important amino acids. In summary, the outcomes indicated that the synthesized analogues exhibited the potential to inhibit PL activity.