Table 1. Inhibitory activities of the type I and type II compounds against DNA gyrase from E. coli.

Compound	Type	R1	R2	R3	IC50 a (μM) or RA b (%)
5 c	I	H	COOCH3	—	IC50 = 88 ± 19
6	I	H	CONHNH2	—	RA = 100
7	I	H		—	IC50 = 8.6 ± 2.4
8 c	I	H	COOH	—	IC50 = 1.4 ± 0.2
14	I	OBzl	COOCH3	—	RA = 100
15	I	OBzl	CONHNH2	—	RA = 100
16	I	OBzl		—	RA = 85
17	I	OBzl	COOH	—	IC50 = 0.86 ± 0.02
25	II	—	—	COOCH3	IC50 = 0.086 ± 0.011
26	II	—	—	CONHNH2	IC50 = 0.14 ± 0.02
27	II	—	—		IC50 = 0.045 ± 0.022
28	II	—	—	COOH	IC50 = 0.020 ± 0.009
Novobiocin					IC50 = 0.17 ± 0.02

^aConcentration of compound that inhibits the enzyme activity by 50%.

^bResidual activity of the enzyme at 10 μM concentration of the compound.

^cPreviously published results.20