Synthesis and bioactivities of heterocyclic lipids as PAF antagonists. 2

Conformationally constrained analogues of platelet activating factor incorporating a lipophile and a pyridine-like heterocycle linked to core groups such as 1,1-bis(hydroxymethyl)cyclobutane and 2,4-bis(hydroxymethyl)-oxetane, -thietane and -azetidine skeletons via hydrogen bond acceptors such as ether and/or carbamate have been synthesized, and their in vitro and in vivo bioactivitites have indicated potent and selective PAF antagonism.