Design, synthesis, and biological evaluation of new quinoline-based heterocyclic derivatives as novel antibacterial agents

A novel series of quinolone-based heterocyclic derivatives including thiadiazine, thiadiazoles, and triazole were synthesized and their in vitro antibacterial activity against Gram-positive and Gram-negative bacteria were evaluated. Newly synthesized derivatives have been obtained in good yields ranging from 65 to 80%. The synthesized derivatives have been characterized and their structures identified using spectroscopic analysis including NMR, FT-IR, and mass techniques. Most of compounds exhibited moderate-to-good antibacterial activity against all four bacterial strains and are significantly more active than ampicillin. Compounds showed relatively good anti-bacterial activity compared to moderate activity of other compounds. The results obtained herein are important for further structure modifications of quinoline bearing heterocyclic moiety and the exploitation of the therapeutic potential of quinoline derivatives as antibacterial agents. Graphic abstract