Synthesis and bioactivities of heterocyclic lipids as PAF antagonists. 1

Conformationally constrained analogues of platelet activating factor incorporating various combinations of a lipophile and a pyridine-like heterocycle via hydrogen bond acceptors such as ether and/or carbamate linked to a suitable core group such as 1,1-bis(hydroxymethyl)cycloalkane and 3,3-bis(hydroxymethyl)-oxetane, -thietane and -azetidine skeletons have been synthesized, and are shown to be powerful and selective PAF receptor antagonists.