TABLE 5.

EGFR inhibitory activities of compounds 3b, 3d, 3e and 3l.

Compd no.	R1	R2	R3	R4	IC50 (μM)
					EGFR
					1 h	2 h
3b	H	H	Cl	H	3.26		71.74
3d	OCH3	H	H	H	5.14		25.97
3e	Cl	H	H	H	1.29		4.41
3l	H	H	CF3	H	0.42		1.67
icotinib	—	—	—	—	0.00138		0.038

Kinase inhibitory activities of compounds were evaluated using the enzyme-linked immunosorbent assay (ELISA).