Table 3.

Biological Activity of Quinolone R₂ Carboxylic Acids and Methyl Esters with R₁ Substituted Pyridines^a

			DHODH Assay			MTT Assay
#	R1	R2	IC50 (μM)	cLogP	LipE	HCT-116 IC50 (μM)	MIA PaCa-2 IC50 (μM)
22		CO2H	0.148 ± 0.021	5.14	1.69	4.63 ± 1.1	8.84 ± 3.8
23		CO2H	1.43 ± 0.76	5.14	0.70	3.87 ± 1.0	8.71 ± 3.2
24		CO2Me	>50	5.37	NA	NTb	NT
25		CO2H	0.373 ± 0.22	4.46	1.97	10.8 ± 2.7	17.9 ± 5.9
26		CO2H	0.0221 ± 0.020	4.46	3.20	10.0 ± 0.85	18.2 ± 6.0
27		CO2H	12.5 ± 1.1	4.40	0.50	16.8 ± 2.9	> 100
28		CO2H	1.42 ± 0.37	4.40	1.45	11.2 ± 2.6	32.1 ± 24
29		CO2H	0.0327 ± 0.021	4.72	2.77	3.30 ± 0.75	7.13 ± 1.4
30		CO2H	0.235 ± 0.11	5.22	1.41	5.13 ± 3.1	14.2 ± 7.3
31		CO2H	8.4 ± 3.2	3.52	1.56	> 100	> 100

^aData for cLogP values was predicted using ChemBioDraw Professional 16. Lipophilic ligand efficiency (LipE) calculated LipE = −pIC₅₀ (M) – cLogP.³³

^bNT, not tested.