will also be appreciated that the nucleus in the compounds of the invention may be depicted as str22 the compounds of this invention are cardiovascular agents useful as platelet aggregation inhibitors e g for treatment of thrombotic disease such as coronary or cerebral thromboses in addition the compounds of the invention are useful in inhibiting bronchoconstriction such as associated with asthma and airways hyperreactivity they are also selective thromboxane a 2 receptor antagonists e g having a vasodilatory effect for treatment of myocardial ischemic disease such as angina pectoris in addition the compounds of the invention may be useful in improving post ischemic myocardial dysfunction for example decreased contractile dysfunction decrease in tissue necrosis and decrease in infarct size preventing or treating toxemia in pregnancy preventing or reducing platelet loss during extracorporeal circulation potentiating diuretic induced diuresis preventing or reducing adverse reactions to protamine preventing nephrotoxicity of drugs such as cyclosporine a gentamycin and the like preventing thrombosis and adverse reactions to radiographic contrast agents preventing or reducing venous thrombosis in conjunction with heparin treating burn injury and promoting wound healing treating ischemia alone or in combination with a calcium channel blocker preserving vascular patency and circulation during and following vascular surgery preventing reperfusion injury after cns ischemic states like stroke or vascular surgery treating tardive dyskenesia treating raynaud 39 s disease treating unstable angina treating purpura fulminarus and treating thrombotic thrombocytopenia purpura furthermore the compounds of the invention may be useful in the treatment of pulmonary embolism diabetic retinopathy nephritis and in coronary artery by pass renal dialysis thrombolysis endarterectomy acute renal failure lupus peripheral vascular disease intermittent claudication pulmonary hypertension after mitral valve surgery pulmonary hypertension after intralipid infusion subarachnoid hemorrhage treating or preventing complications following organ transplant particularly cardiac or renal treating persistent pulmonary.