Table 4.

Substitution effect of R₅

Compound	R5	LcrF IC50 (μM)
14	H	3.9a
36	CH3	7.6a
37	OCH2CH3	17.1a
38	F	26.6b
39	N(CH3)2	66.0b
40	N(CH3)CH2CH2N(CH3)2	3.3c
41	OCH2CH2( 1 -methyl-4-piperazine)	3.1c

^aIC₅₀ was determined using a dose response analysis with a maximum concentration of 25 μg/mL

^bIC₅₀ determined with a maximum concentration of 50 μg/mL

^cNon-specific DNA binding. Data represent the average values from two independent experiments unless specified otherwise in the Experimental section.