Synthesis and biological activity of the platelet-activating factor antagonist (±)-trans-2-(3-methoxy-4-phenylsulfonylethoxy-5-n-propylsulfonylphenyl)-5-(3,4,5-trimethoxyphenyl)tetrahydrofuran (L-671,284) and its analogs

(+/-)-trans-2-(3-Methoxy-4-phenylsulfonylethoxy-5-n-propylsulfonylphenyl)tetrahydrofuran (L-671,284) is a highly potent, selective, competitive PAF-receptor antagonist with a K(i) of 1.0 nM for inhibition of binding of [H-3]C18-PAF to human platelets and exhibits little or no gender differences in bioactivities in rats. Several 4' positional analogs of L-671,284 have been synthesized and evaluated in vitro.