IN-VITRO ACTIVITIES OF THE OXAZOLIDINONE ANTIBIOTICS U-100592 AND U-100766 AGAINST STAPHYLOCOCCUS-AUREUS AND COAGULASE-NEGATIVE STAPHYLOCOCCUS SPECIES

U-100592 and U-100766 are closely related antibiotics of the oxazolidi none class. Their in vitro activities were determined against 100 isol ates of Staphylococcus aureus end 100 isolates of coagulase-negative S taphylococcus species by broth and agar dilution test methods. The MIC s of both compounds by either test method at which 50 and 90% of isola tes are inhibited were 2 and 4 mu g/ml, respectively, for S. aureus an d 1 to 2 mu g/ml for coagulase-negative staphylococci. Time-kill assay s with selected strains indicated a primarily bacteriostatic effect ag ainst staphylococci.