Synthesis of isatin–quinoline conjugates as possible biologically active agents

A series of 12 new 2-methyl-N′-((3Z)-2-oxo-1,2-dihydro-3H-indol-3-ylidene) quinoline-3-carbohydrazide derivatives (7a–l) were synthesized by the condensation of quinolinyl hydrazide (6) with different isatins (3a–l) and characterized by physical and spectral data (FT-IR, 1H NMR, and mass). The synthesized compounds were evaluated for in vitro antimicrobial and in vivo anti-inflammatory activity. Tested compounds exhibited moderate to good anti-bacterial and anti-fungal activity. Evaluation of the compounds revealed remarkable anti-inflammatory activity and were comparable with standard, indomethacin. Compounds 7l, 7b,7d, and 7c inhibited paw edema in a carrageenan-induced rat hind paw edema model.