Table 10. Achillion isothiazoloquinolone SAR for MRSA (MIC) and cytotoxicity in Hep2 cells.

Compound	R7	MRSAa MIC (µg/ml)	Hep2b CC50 (µg/ml)c	Compound	R7	MRSAa MIC (µg/ml)	Hep2b CC50 (µg/ml)c
75		16	>35	83		8.0	2
76		0.125	3	84		32	>38
77		0.25	>37	85		>64	4
78		0.125	2	86		0.25	19
79		4.0	10	87		4.0	3
80		2.0	35	88		1.0	>40
81		0.5	13	89		2.0	>35
82		4.0	20	90		1.0	4

^aMethicillin resistant S. aureus (methicillin- and quinolone-resistant, vancomycin intermediate-resistant; ^bHep2 = human laryngeal carcinoma cell line; CC₅₀ = concentration of drug lethal to 50% of cells; 72h incubation with drug; ^cvalues originally reported as μM were converted to μg/ml for this table.