Table 1.

Inhibition of platelet aggregation and P2 receptor selectivity by diadenosine 5′,5‴-P¹,P⁴-tetraphosphate (Ap₄A) and its analogs

	Platelet aggregation	P2Y12 VASP	P2Y1 Ca2+ flux
	IC50 (μM) (95% CI)	IC50 (μM) (95% CI)	IC50 (μM) (95% CI)
Ap4A	7.9 (5.5–11.4)	> 250	32.5 (22.1–47.8)
Compound 1	2.8 (2.0–4.0)	88.6 (59.8–131.3)	2.9 (2.0–4.2)
Compound 2	1.3 (1.0–1.7)	19.3 (10.2–36.5)	111.5 (51.8–239.9)
Compound 3	0.66 (0.43–1.01)	23.9 (12.8–44.3)	57.2 (15.5–211.5)
Compound 4	0.12 (0.08–0.17)	6.4 (3.7–11.4)	10.2 (6.7–15.7)

CI, confidence interval; VASP, vasodilator-stimulated phosphoprotein. Compounds: 1, diadenosine 5′,5‴-P¹,P⁴-dithiotetraphosphate; 2, diadenosine 5′,5‴-P²,P³-chloromethylenetetraphosphate; 3, diadenosine 5′,5‴-P¹-thio-P²,P³-chloromethylenetetraphosphate; 4, diadenosine 5′,5‴-P¹,P⁴-dithio-P²,P³-chloromethylenetetraphosphate.