Table 3.

IC₅₀ values of radioligand displacement calculated for A_2A receptor.

Compound	IC50 [μM]	Compound	IC50 [μM]
7	>100	23	>100
8	74.1 ± 9.7	24	22.0 ± 4.4
15	>100	35	n.d
16	26.5 ± 5.1	37	>100
17	>100	39	>100
18	14.6 ± 0.6	40	20.3 ± 0.5

IC₅₀ – Compound concentration that inhibits radioligand binding to the receptor by 50%. n.d. – not determined.