Table 1.

1H-Imidazo[4,5-c]quinolin-4-amine Derivatives Synthesized and Effects on Agonist-Induced A₃AR Activation

Compound	R2	R1	Emaxa(%)
2-alkyl and 2-cycloalkyl derivatives
13	3,4-Cl2		153 ± 12*
14	3,4-Cl2		216 ± 12*
15	3,4-Cl2		159 ±13*
16	3,4-Cl2		150 ± 5*
17	3,4-Cl2		111 ± 16
5	3,4-Cl2		109 ± 3
6	3,4-Cl2		142 ± 5*
7	3,4-Cl2		225 ± 10*
8	3,4-Cl2		175 ± 3*
18	3,4-Cl2		241 ± 9*
19	3,4-Cl2		146 ± 2*
20	3,4-Cl2		241 ± 12*
21	3,4-Cl2		135 ± 7*
22	3,4-Cl2		122 ± 6*
23	3,4-Cl2		101 ± 3
2-bicycloalkyl derivatives
24	3,4-Cl2		187 ± 14*
25	3,4-Cl2		170 ± 6*
26	3,4-Cl2		154 ± 7*
27	3,4-Cl2		237 ± 12*
28	3,4-Cl2		219 ± 16*
29	3,4-Cl2		187 ±8*
2-cycloalkyl derivatives with hydrophilic substitution
30	3,4-Cl2		136 ± 11
31	3,4-Cl2		173 ± 14*
32	3,4-Cl2		160 ± 16*
33	3,4-Cl2		118 ± 14
34	3,4-Cl2		156 ± 10*
2-alkyl and 2-cycloalkyl derivatives with modified 2-arylamino groups
35	4-I		184 ± 9*
36	4-Br		207 ± 17*
37			164 ± 10*
38			170 ± 12*
39	4-I		223 ± 10*
48	4-Sn(CH3)3		ND
49	4-Sn((CH2)3CH3)3		ND

^aEffect of PAM derivative (1.0 μM) on [³⁵S]GTPγS binding induced by 52 using WT hA₃ARs (n = 3).

^*P ≤ 0.05 (one-way ANOVA with Bonferroni-adjusted t test for multiple comparisons) with respect to control in the absence of a PAM. Effects of 0.1 and 10 μM are shown in Table S4. ND, not determined.