Table 1.

Inhibition potencies of thymidine analogs for vaccinia virus and human TMP kinases

Inhibitor	Ki for Vacc TMP kinase	Ki for human TMP kinase, mM
dT	25 ± 5 μM	0.25
dU	1.0 ± 0.1 mM	2.5
5F-dU	0.7 ± 0.1 mM	>5
5Br-dU	7 ± 1 μM	0.2
5Cl-dU	15 ± 5 μM	0.37
5I-dU	23 ± 2 μM	0.35
BVdU	0.5 ± 0.1 mM	1.1 ± 0.1
5I-BrV-dU	0.5 ± 0.05 mM	0.3 ± 0.05
5diIV-dU	0.6 ± 0.1 mM	0.35 ± 0.15

Activities were measured in standard conditions with [ATP] = 1 mM, [TMP] from 10 μM to 1 mM, and varying inhibitor concentrations (0-5-50 μM for the more efficient). K_I values were obtained from double reciprocal plots. Shown in italics are data from ref. 41.