Table 1.

In Vitro Pharmacological Data for Antagonism of Turkey Erythrocyte P2Y₁ Receptors, Indicated by the Inhibition of PLC Stimulation Elicited by 30 nM 2-MeSADP, for at Least Three Separate Determinations. “P” = Phosphate

Compound	R =	R′ =	Antagonist Effect,a % of max.	IC50, μM (n = 3, unless noted)
5		Cl	100	4.56 ± 1.38
6		H	100	1.09 ± 0.51
7		Cl	100	0.48 ±0.13
8		Cl	68 ±7	22.6+ 14.6
9		Cl	78 ±7	31 + 11
10		Cl	65 ±8	37.6 + 12.6
11		Cl	100	0.23 ±0.10
3		H	100	1.60 ± 0.47
4		Cl	99 ± 1	0.84 ±0.13
12		Cl	100	2.04 ± 0.94 (4)
13		Cl	100	7.86 ±3.13
14		Cl	100	1.47 ± 0.43
15		Cl	100	2.10 ±0.97
16		Cl	100	1.74 ± 0.80
17		Cl	100	2.17 ±0.85
18		Cl	100	2.70 ± 0.66
19		Cl	100	2.36 ± 0.63
20		Cl	100	1.90 ±0.24

^aAt 100 μM, none of the acyclic adenosine bisphosphate nucleotide analogues displayed agonist activity at the P2Y₁ receptor in turkey erythrocyte membranes.