Biological evaluation of isothiazoloquinolones containing aromatic heterocycles at the 7-position: In vitro activity of a series of potent antibacterial agents that are effective against methicillin-resistant Staphylococcus aureus

We synthesized a diverse series of 9H-isothiazolo[5,4-b]quinoline-3,4-diones containing heteroaromatic groups at the 7-position via palladium-catalyzed cross-coupling. Many of these compounds demonstrated potent antistaphylococcal activity (MICs ⩽2 μg/mL) against a multi-drug-resistant strain (ATCC 700699) and low cytotoxic activity (CC50 > 100 μM) against the human cell line Hep2 (laryngeal carcinoma).

Several of the reported analogues demonstrate strong in vitro antistaphylococcal activity, particularly against MRSA, and low cytotoxicity.Figure optionsDownload as PowerPoint slide