Design, synthesis, and antibacterial activity of novel 8-methoxyquinoline-2-carboxamide compounds containing 1,3,4-thiadiazole moiety.

A series of novel 8-methoxyquinoline-2-carboxamide compounds containing 1,3,4-thiadiazole moiety was designed and synthesized by using an active substructure combination method. Then, the antibacterial activities of all the target compounds were evaluated in vitro against three Gram-positive bacteria and three Gram-negative bacteria. The antibacterial assay showed that some target compounds displayed moderate to good antibacterial efficacy in comparison with the reference drug Chloromycin. Some interesting results of structure-activity relationships were also discussed.