(5Z)-7-(2,2-Dimethyl-4-phenyl-1,3-dioxan-cis-5-yl)heptenoi c acid: a specific thromboxane A2 receptor antagonist

(5Z)-7-(2,2-Dimethyl-4-phenyl-1,3-dioxan-cis-5-yl)heptenoic acid (2) was found to be a specific, competitive thromboxane A2 receptor antagonist that acts at platelet, vascular, and pulmonary receptors. No antagonism was detected at receptors for prostacyclin, SRSA, norepinephrine, and serotonin. The synthesis of a series of analogues is described; activity at the thromboxane receptor was observed in cis-substituted compounds but not in their trans counterparts. Compound 2 inhibited the bronchoconstriction induced by a stable thromboxane mimetic in the anesthetized guinea pig.