9,11-Iminoepoxyprosta-5,13-dienoic acid is a selective thromboxane A2 synthetase inhibitor

9,11-Iminoepoxyprosta-5,13-dienoic acid inhibits the thromboxane A2 synthetase in platelet and lung microsomal enzyme preparations and in intact platelets. It does not inhibit the protaglandin I2 synthetase in aorta or lung microsomes and intact Balb 3T3 fibroblasts. In lung microsomes, which contain both enzymes, 9,11-iminoepoxyprosta-5,13-dienoic acid inhibits only thromboxane A2 formation and augments prostaglandin I2 formation. This inhibitor is more selective than other reported prostaglandin endoperoxide analogs which inhibit the platelet thromboxane synthetase.