Selective A2 Adenosine Receptor Agonists with Potent Inhibitory Activity on Platelet Aggregation

  • Gloria Cristalli
  • Emidio Camaioni
  • Sauro Vittori
  • Rosaria Volpini


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 selectivity[1]Table 17-1 shows the ability of HENECA to inhibit the binding of radioligands to A1 and A2 receptors compared with that of NECA [2], 2-[[4-(2carboxyethyl) phenethyllamino) adenosine-5’N-ethyluronamide (CGS 21680) [3]and of the selective A1 agonist 2-chloro-N6-cyclopentyladenosine (CCPA) [4] In the same table the effects of these compounds on the stimulation of platelet and PC 12 cell membrane adenylate cyclase are also shown [5]. 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.


Platelet Aggregation Adenosine Receptor Potency Ratio Potent Inhibitory Activity Adenosine Receptor Agonist 
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© Springer Science+Business Media New York 1995

Authors and Affiliations

  • Gloria Cristalli
  • Emidio Camaioni
  • Sauro Vittori
  • Rosaria Volpini

There are no affiliations available

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