Synthesis and bioactivity evaluation of novel acetamide-derived compounds bearing a methylsulfonyl unit

This study reports the synthesis and structural characterization of a series of novel acetamide-derived compounds containing a methylsulfonyl unit. The in vitro antibacterial activity results demonstrated that compound 2-((4-fluorophenyl)sulfonyl)-N-(4-(methylsulfonyl)phenyl)acetamide (6b) exhibited superior antibacterial activities against Xanthomonas oryzae pv. oryzicolaby (Xoc), Xanthomonas oryzae pv. oryzae (Xoo), and Xanthomonas axonopodis pv. citri (Xac) at 100 μg/mL concentration, with the inhibition rates of 86.24%, 81.59%, and 75.65%, respectively, compared to Bismerthiazol and Thiodiazole copper. Meanwhile, the in vitro antifungal activities of all target compounds were found to be lower against Mucor fragilis (M. fragilis), Mucor bainieri (M. bainieri), and Trichoderma atroviride (T. atroviride) at 50 μg/mL concentration, with the inhibition rates of 0–45.21%, 0–30.24%, and 0–12.65%, respectively, compared to Carbendazim. Moreover, bioassay results of the target compounds against prostate cancer (PC3), hepatocellular carcinoma (HepG2), and leukemia (K562) cells at 10 μM concentration demonstrated that, compared to 5-fluorouracil, compound 2-((4-fluorophenyl)thio)-N-(4-(methylsulfonyl)phenyl)acetamide (4c) illustrated obvious antitumor activity (56.87%) against K562. This work first highlights the effect of the modification of the acetamide-derived compounds bearing a methylsulfonyl unit on the bioactivity evaluation.