Selective A2 Adenosine Receptor Agonists with Potent Inhibitory Activity on Platelet Aggregation
Recently, we have reported on the synthesis of the 2-hexynyl derivative of NECA, N-ethyl-l’deoxy-1’ -(6-amino-2-hexynyl-9H-purin-9-yl)-ßribofuranuronamide, identified as HENECA (Fig. 17-1), which was shown to possess high affinity at A2 adenosine receptors combined with a good A2 versus A1 selectivityTable 17-1 shows the ability of HENECA to inhibit the binding of radioligands to A1 and A2 receptors compared with that of NECA , 2-[[4-(2carboxyethyl) phenethyllamino) adenosine-5’N-ethyluronamide (CGS 21680) and of the selective A1 agonist 2-chloro-N6-cyclopentyladenosine (CCPA)  In the same table the effects of these compounds on the stimulation of platelet and PC 12 cell membrane adenylate cyclase are also shown . The results of the cyclase assays are in good agreement with the higher affinity of HENECA of the A2 receptors compared with the other adenosine agonists listed in Table 17-1.
KeywordsPlatelet Aggregation Adenosine Receptor Potency Ratio Potent Inhibitory Activity Adenosine Receptor Agonist
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