Table 2. IC₅₀ Values of Compounds 15a–d, SAHA, and CX-4945 against Four Human Tumor Cell Lines.

	IC50 values (μM)
Cpd	LNCaP	PC3	MCF-7	A549
15a	>100	>100	>100	>100
15b	>100	>100	>100	>100
15c	16.31 ± 0.7	40.42 ± 4.4	52.48 ± 10.0	104.73 ± 7.9
15d	66.70 ± 5.0	>100	>100	>100
SAHA	0.69 ± 0.1	2.03 ± 0.1	1.26 ± 0.1	3.14 ± 0.2
CX-4945	6.52 ± 0.6	10.87 ± 0.6	9.41 ± 0.3	11.60 ± 1.8