Table 1. In Vitro Kinase Inhibition of Compounds 6a–6k against DDR1^a and Abl1^b.

					kinase inhibition (IC50, nM)
compd	X	Y	R1	R2	DDR1	Abl1
6a	N	N	H	(4-methylpiperazin-1-yl)methyl	442 ± 69	>10000
6b	N	N	(R)-Me	(4-methylpiperazin-1-yl)methyl	24.3 ± 4.1	>10000
6c	N	N	(S)-Me	(4-methylpiperazin-1-yl)methyl	309 ± 44	>10000
6d	N	N	(R)-Et	(4-methylpiperazin-1-yl)methyl	36.4 ± 5.7	>10000
6e	N	N	(S)-Et	(4-methylpiperazin-1-yl)methyl	>2000	>10000
6f	N	N	(R)-i-Pr	(4-methylpiperazin-1-yl)methyl	>1000	>10000
6g	N	N	(S)-i-Pr	(4-methylpiperazin-1-yl)methyl	>3000	>10000
6h	N	C	H	(4-methylpiperazin-1-yl)methyl	328 ± 35	>10000
6i	C	C	H	(4-methylpiperazin-1-yl)methyl	>3000	>10000
6j	N	N	(R)-Me	4-methyl-1H-imidazol-1-yl	9.4 ± 1.7	>10000
6k	N	N	(S)-Me	4-methyl-1H-imidazol-1-yl	326 ± 43	>10000
1(13)					9.7 ± 2.3	308 ± 42

^aDDR1 experiments were performed using the LANCE ULTRA kinase assay, according to the manufacturer’s instructions. The data are the means from at least two independent experiments.

^bAbl1 activity experiments were performed using the FRET-based Z-Lyte assay, according to the manufacturer’s instructions. The data are the means from at least 3 independent experiments.