Table 2. In Vitro Cytotoxic Potency of the Newly Synthesized Compounds 2–8 against Various Human Cancer Cell Lines and Normal Cells Representing SI of the Most Active Derivatives^a.

	IC50 (mean ± SEM) (μM)
compd. no.	HepG-2	PC-3	MCF-7	A-549	PBMC
2a	57.85 ± 0.07	26.82 ± 2.21	37.73 ± 0.08	34.57 ± 0.06	121.34 ± 11.35
2b	60.85 ± 0.06	44.50 ± 3.51	55.44 ± 0.04	57.48 ± 0.05	133.30 ± 13.67
2c	47.66 ± 0.04	25.44 ± 0.04	21.76 ± 0.08	27.81 ± 0.04	144.56 ± 14.89
2d	34.77 ± 0.03	39.32 ± 0.0	24.74 ± 0.08	20.84 ± 0.04	157.78 ± 16.35
2e	37.76 ± 0.05	40.56 ± 0.05	25.64 ± 0.08	25.96 ± 0.05	168.54 ± 17.36
3	37.73 ± 0.02	17.29 ± 0.03	6.59 ± 0.07	10.42 ± 0.05	179.25 ± 18.75
4	56.65 ± 0.04	25.41 ± 0.05	8.32 ± 0.04	15.61 ± 0.06	186.68 ± 19.36
5a	35.66 ± 0.04	16.49 ± 0.05	5.42 ± 0.05	10.37 ± 0.04	174.90 ± 18.24
	SI = 4.90	SI = 10.60	SI = 32.26	SI = 16.86
5b	38.49 ± 0.02	18.22 ± 0.03	4.18 ± 0.03	8.27 ± 0.03	165.76 ± 17.36
	SI = 4.30	SI = 9.09	SI = 39.65	SI = 20.04
5c	27.59 ± 0.04	18.44 ± 0.04	4.33 ± 0.04	12.30 ± 0.04	146.32 ± 16.15
	SI = 5.23	SI = 7.93	SI = 33.79	SI = 11.89
6a	10.48 ± 0.03	16.30 ± 0.09	4.30 ± 0.04	5.20 ± 0.03	157.45 ± 16.89
	SI = 15.02	SI = 9.65	SI = 36.61	SI = 30.27
6b	5.47 ± 0.02	13.21 ± 0.06	1.29 ± 0.03	3.18 ± 0.03	178.23 ± 17.69
	SI = 32.58	SI = 13.49	SI = 138.16	SI = 56.04
6c	7.73 ± 0.04	26.41 ± 0.05	2.51 ± 0.06	5.80 ± 0.05	187.67 ± 19.76
	SI = 24.27	SI = 7.10	SI = 74.76	SI = 32.35
7	29.75 ± 0.03	17.90 ± 0.03	4.65 ± 0.07	7.43 ± 0.04	165.23 ± 18.05
8a	59.84 ± 0.05	36.55 ± 0.03	13.75 ± 0.08	25.46 ± 0.05	173.45 ± 18.95
	SI = 2.91	SI = 4.74	SI = 12.61	SI = 6.81
8b	60.48 ± 0.05	42.56 ± 0.06	17.95 ± 0.04	37.21 ± 0.03	196.67 ± 20.67
	SI = 3.25	SI = 4.62	SI = 10.95	SI = 5.28
8c	45.49 ± 0.04	32.48 ± 0.04	10.31 ± 0.04	8.29 ± 0.03	188.89 ± 19.86
	SI = 4.15	SI = 5.81	SI = 18.32	SI = 22.78
8d	47.86 ± 0.05	39.55 ± 0.08	14.77 ± 0.05	9.50 ± 0.06	179.09 ± 18.96
	SI = 3.74	SI = 4.52	SI = 12.12	SI = 18.85
DOX	4.51 ± 0.26	8.11 ± 0.05	4.17 ± 0.2	8.20 ± 0.08	250.00 ± 26.56
	SI = 55.43	SI = 30.82	SI = 59.95	SI = 30.48
erlotinib	8.19 ± 0.4	8.89 ± 0.6	4.16 ± 0.2	3.76 ± 0.2	45.75 ± 26.56
	SI = 5.58	SI = 5.14	SI = 10.99	SI = 12.16

^aDOX: doxorubicin; IC₅₀: compound concentration required to inhibit the cell viability by 50%; SEM: standard error mean; each value is the mean of three independent determinations; SI: selectivity index.