Table 2. Structures and activities for 4-thiazolidinone analogs 16–32.

Compd	R	Inhibitory rate at 10 μM (%)	hDHODH IC50 a (μM)
16		40.010	>10
17		18.377	>10
18		34.109	>10
19		56.856	8.51
20		49.438	10.64
21		68.979	2.68
22		74.431	3.03
23		62.932	4.41
24		52.475	9.45
25		40.378	>10
26		79.074	1.75
27		15.064	>10
28		43.738	>10
29		45.360	>10
30		21.886	>10
31		80.327	1.12
32		25.632	>10

^aIC₅₀ values were determined from three independent tests, and attempts to determine IC₅₀ values were made if the inhibition rate at 10 μM was higher than 50%.