Table 1.

RET SAR for compounds 6a–g and 13a–g.^a

<!–Col Count:2– > Compound	RET IC50 (µM)
6a	>100
6b	>100
6c	>100
6d	67.8 ± 1.1
6e	18.8 ± 4.6
6f	15.7 ± 2.9
6g	0.21 ± 0.04
13a	22.3 ± 7.7
13b	20.4 ± 5.6
13c	19.3 ± 2.8
13d	17.2 ± 3.1
13e	14.3 ± 1.9
13f	9.1 ± 2.6
13g	0.75 ± 0.03
Vandetanib	0.102 ± 0.008

^aIC₅₀ values represent the concentration required to inhibit enzyme activity by 50%. The screening was completed at 9 µM ATP concentration in duplicate.