Quinoline based furanones and their nitrogen analogues: Docking, synthesis and biological evaluation.

A small library of twenty-four quinoline based butenolides also known as furanones and their nitrogen analogues was prepared by using two different aroylpropionic acids, viz. 3-(2-naphthoyl)propionic acid ( 3 ) and 3-(biphenyl-4-yl)propionic acid ( 4 ), as starting materials. The 3-aroylpropionic acids were reacted with different 6-substituted-2-chloroquinolin-3-carbaldehydes ( 2a–d ) to obtain the corresponding furan-2(3 H )-ones ( 5a–h ). The purified and characterized furanones were then converted into their corresponding 2(3 H )-pyrrolones ( 6a–h ) and N -benzyl-pyrrol-2(3 H )-ones ( 7a–h ). The antimicrobial activities of the title compounds were evaluated against two strains of each Gram +ve ( Staphylococcus aureus and Bacillus subtilis ), Gram −ve bacteria ( Escherichia coli and Pseudomonas aeruginosa ) and against fungal strains of Aspergillus niger and Aspergillus flavus . In vivo anti-inflammatory potential of the title compounds was investigated by standard method. Majority of the compounds showed significant antibacterial activity against both the Gram +ve strains. Eight most potent anti-inflammatory compounds ( 5b, 5d, 5h, 6b, 7b, 7d, 7f, 7h) which exhibited >53% inhibition in edema, were also screened for their in vivo analgesic activity. All the tested compounds were found to have significant reduction in ulcerogenic action but only three compounds ( 5d, 5h and 7h ) showed comparable analgesic activity to standard drug, diclofenac. The results were also validated using in silico approach and maximum mol doc score was obtained for compounds 7a–h . On comparing the in vivo and in silico anti-inflammatory results of synthesized compounds, N -benzyl pyrrolones ( 7a–h ) emerged as the potent anti-inflammatory agents. It was also observed that compounds that possess electron withdrawing group such as Cl or NO 2 are more biologically active. [ABSTRACT FROM AUTHOR]