Table 2.

IC₅₀ of stereoisomers against proteins and glioblastoma cell lines^a.

Cell line	IC50 (μmol/L)
	R1 = 5-Cl				R1 = 5-Br
	4d	Ent-4d	4d′	Ent-4d′	4g	Ent-4g	4g′	Ent-4g′
MDM2	0.52 ± 0.07	0.13 ± 0.04	1.8 ± 0.12	1.5 ± 0.20	0.28 ± 0.06	0.08 ± 0.02	2.5 ± 0.3	1.3 ± 0.4
CDK4	0.78 ± 0.11	0.49 ± 0.13	3.9 ± 0.42	2.6 ± 0.37	0.32 ± 0.05	0.25 ± 0.08	10.6 ± 0.9	3.7 ± 0.6
U87MG	8.3 ± 1.5	6.1 ± 1.3	60.4 ± 4.8	41.6 ± 3.9	4.9 ± 0.5	3.6 ± 0.7	>50	28.6 ± 2.5
U251	17.8 ± 3.2	12.6 ± 2.3	>50	>50	8.6 ± 0.8	5.8 ± 1.1	>50	>50

^aEach compound was tested in triplicate; data are mean ± SD (n = 3). The IC₅₀ value of anti-proliferation assays was obtained after 24-h incubation.