Moreover, the dominating significance of the oxidation of arachidonic acid in the aggregation of thrombocytes has recently been revealed [5-7]. It has been established that the use of inhibitors of the free-radical oxidation of lipids is promising for the treatment of disruptions of the aggregation of thrombocytes. We have synthesized the following phenylmercaptoacetic acid derivatives: gococHt-X-CEtCOOH (7-~) z: x=-s-@--@ s-~ 2: x=- ...