Table 1

Table 1. Comparison of fluoroquinolone MIC and MPC with Staphylococcus aureus

Fluoroquinolone	MIC^a	MPC^b	MPC/MIC
Norfloxacin	0.31	7.0	23
Ciprofloxacin	0.12	0.9	7.5
PD160793 (C-8-H)^c	0.21	1.0	4.8
PD161148 (C-8-OMe)^d	0.11	0.4	3.6

aMIC₉₉(m g/ml), concentration at which growth of 99% of the cells is blocked
^bMPC₁₀¹⁰(m g/ml), concentration at which no resistant mutant is recovered when 10¹⁰ cells are applied to fluoroquinolone-containing agar plates.
^cStructure is similar to ciprofloxacin, but an ethyl group is attached to the C-7 piperazinyl ring.
^dIdentical to PD160793 except that a methoxy group (OMe) is attached to carbon 8.