Synthesis and characterization of biologically active flurbiprofen amide derivatives as selective prostaglandin-endoperoxide synthase II inhibitors: In vivo anti-inflammatory activity and molecular docking

Abstract

A novel series of twenty two flurbiprofen amides (1-22) were designed and synthesized in good to excellent yields by reacting flurbiprofen acid with various aromatic/aliphatic primary amines in the presence of 1,1‑carbonyldiimidazole (CDI) in basic medium using acetonitrile as solvent. Structures of the synthesized derivatives were elucidated with the help of HR-ESI-MS, ¹H-, and ¹³C NMR spectroscopy and finally screened them for their in-vivo anti-inflammatory potential using carrageenan induced mice paw oedema assay. Among the series, four compounds (8, 14, 15, and 20) displayed excellent activity ranging from 59.0 to 77.7 % decrease, while eight compounds (1, 3, 7, 10, 12, 13, 17, and 18) exhibited good activity in the decrease range of 37.0-50.0 %. Additionally, four compounds (2, 6, 16, and 22) attributed less activity, while the remaining six compounds (4, 5, 9, 11, 19, and 21) were found to be inactive. Furthermore, the In-silico studies were executed on the synthesized derivatives in order to explain the binding interface of compounds with the active sites of prostaglandin endoperoxide-synthase II enzyme.

Keywords: Anti-inflammatory; Flurbiprofen; Molecular docking; NMR spectroscopy; Synthesis.