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. Author manuscript; available in PMC: 2016 Jul 21.
Published in final edited form as: Bioorg Med Chem Lett. 2001 Sep 3;11(17):2295–2300. doi: 10.1016/s0960-894x(01)00450-4

Table 1.

Affinities of (N)-methanocarba analogues of 6-oxpurine ribosides in radioligand binding assays at rat A1,a rat A2A,b and human A3 receptors,c unless noted, and in other biochemical assay systemsd

graphic file with name nihms803052t1.jpg
Compound R1 R2 Ki (µM) or % displacement at 100 µM
rA1a rA2Ab hA3c
5 MRS 1957 H CH2OH < 10% < 10% 30 ± 10%
6 MRS 1997 H CONHCH3 < 10% < 10% 28.8 ± 5.2
7a MRS 2397d H CH2O–phosphate 11 ± 1%
7b MRS 2398d H CH2O–phosphate]2 dimer 21.6 ± 0.4
8 MRS 1941 NH2 CH2OH < 10% < 10% 20.5 ± 2.1
9 MRS 2351d NH2 CH2O–triphosphate < 10%
10 MRS 1971 — CH2OH 2.97 ± 0.15 < 10% 4.35 ± 0.40
11 MRS 1998 — CONHCH3 24.4 ± 4.8 < 10% 1.86 ± 0.23
12 MRS 2396 — CH2O–triphosphate < 10%
a

Displacement of specific [3H]R-PIA binding to A1 receptors in rat brain membranes, expressed as Ki ± SEM or % (n = 3–5).

b

Displacement of specific [3H]CGS 21680 binding to A2A receptors in rat striatal membranes, expressed as Ki ± SEM or % (n = 3–6).

c

Displacement of specific [125I]AB-MECA binding at human A3 receptors expressed in HEK-293 cells, in membranes, expressed as Ki ± SEM or % (n = 3–5).

d

Selected compounds were examined in HL-60 cells for effects on calcium mobilization. Compounds 7a and 7b (100 µM) were inactive in raising intracellular calcium, while compound 9 (100 µM) caused a rise in intracellular calcium equivalent to 53 ± 18% of the effect of 1 µM UTP (n = 3).