Table 6.

Quantitative Determination of Protein:ligand Binding of Compound 2 Analogs to FGF14 and Na_v1.6 by SPR.

Compound	FGF14			Nav1.6 C-terminal tail
	KD* (μM)	kon (M−1 s−1)	koff (s−1)	KD* (μM)	kon (M−1 s−1)	koff (s−1)
19k	ND	ND	ND	> 200	2.57 × 105	4.49 × 10−3
19e	188.9 ± 3.7	4.61 × 102	9.91 × 10−4	ND	ND	ND
21a	4.05 ± 0.17	4.66 × 103	9.33 × 10−3	16.43 ± 2.05	6.23 × 104	3.57 × 10−3
23a	1.31 ± 0.37	1.79 × 104	9.32 × 10−3	> 200	6.16 × 106	2.73 × 10−3
23b	14.72 ± 1.40	2.58 × 104	2.69 × 10−7	> 200	1.26 × 105	1.45 × 10−3
23d	6.94 ± 1.08	1.62 × 103	5.80 × 10−3	> 200	8.29 × 105	7.94 × 10−3
23e	7.02 ± 1.20	7.35 × 103	1.39 × 10−2	> 200	7.16 × 105	1.70 × 10−4
23f	9.47 ± 1.22	2.17 × 102	2.05 × 10−2	67.34 ± 7.3	2.64 × 103	1.22 × 10−2
23g	11.39 ± 2.15	2.89 × 102	2.04 × 10−2	90.14 ± 10.1	3.40 × 102	4.92 × 10−2

^*The equilibrium dissociation constants (K_D) were calculated using data represented in Figure 6. The K_D shown for each protein:ligand interaction is an average of the values calculated using the simplest Langmuir 1:1 interaction model (K_D = k_off/k_on) and the steady-state saturation model. ND, non-determinable.