Antithrombotic activity of a new pyrazine derivative determined by the mouse antithrombotic assay.

A model of pulmonary microembolization in the mouse induced by infusion of epinephrine and collagen was used to determine antithrombotic activity of indomethacin and acetylsalicylic acid and of two newly synthesized pyrazine derivatives. One of the new agents provided marked protection of mice from thrombotic challenge with epinephrine and collagen. Its effectiveness was higher than acetylsalicylic acid (especially at small doses) but smaller than that of indomethacin. The same compound was similar to acetylsalicyclic acid with respect to the inhibition of in vitro human blood platelet aggregation. The new class of pyrazine derivatives (the so-called pyrazine CH- and NH-acids) appears interesting from the view-point of the studies of platelet aggregation and may yield potential antithrombotic drugs.