Synthesis and biological evaluation of novel N, N'-diarylurea derivatives as potent antibacterial agents against MRSA.

A series of new N, N'-diarylurea derivatives were designed and synthesized, some of which exhibited potent antibacterial activity against the drug-susceptible and drug-resistant Gram-positive strains. Especially, compounds 2c, 2g-2l showed broader antibacterial spectrum and more potent antibacterial activity (MIC = 0.30-2.72 μM) against MRSA and MRSE than the control levofloxacin (MIC = 0.69-22.14 μM). In addition, compounds 2c, 2g, 2h and 2l exhibited much better antibacterial activity (MIC = 1.29-2.86 μM) against VRE (E. faecium) than sorafenib (MIC = 275.37 μM), PK150 (MIC = 5.07-10.13 μM) and SC78 (MIC = 2.40-4.79 μM). More importantly, the low cytotoxicity of compounds on cell lines HeLa and HepG2 implied a relatively wide therapeutic window, which was of high importance for further study.