New 5-hydroxy-2-indolecarbohydrazides as platelet aggregation inhibitors in ethylene glycol

The effect of ethylene glycol on blood platelet aggregation was examined using a previously described method. This method also was used to investigate several derivatives of 2-indolecarbohydrazide in vitro. All compounds inhibited platelet aggregation induced by collagen, epinephrine, or adenosine diphosphate at concentrations below 5 x 10(-4) M.