A series of novel pleuromutilin derivatives containing aryl urea groups was synthesized and their antibacterial
activities were evaluated in vitro against S. aureus ATCC 26113, S.aureus SC, S. albus ATCC 8799 and P. aeruginosa
ATCC 27853. Most of compounds exhibited more potent activities than reference drug tiamulin against S. aureus ATCC
26113 and S. aureus SC. Especially, compounds 12f and 12h containing pyridyl urea group and compound 12j with
quinolinyl urea group showed excellent activity with the MIC value less than 0.001μg/ml against S. aureus SC.