Synthesis of a novel series of 3-oxo-2,4-dioxobicyclo[3.2.1]octanes: additional evidence for two thromboxane receptor subtypes.

Abstract A series of 3-oxo-2,4-dioxobicyclo[3.2.1]octanes ( 1–4 ) was synthesized and identified as potent thromboxane (TXA 2 ) receptor agonists. Replacement of the terminal -COOH group resulted in an unexpected change in biological activity: platelet aggregation, which typically occurs in response to TP-receptor stimulation, did not occur although potent contractile properties on vascular smooth muscle were retained.