γ-Pyrone compounds. II: Synthesis and antiplatelet effects of tetraoxygenated xanthones

Article abstract of DOI:10.1002/jps.2600811114

Norathyriol and its analogues, 1,3,5,6-, 3,4,5,6-, 3,4,6,7- and 2,3,6,7- tetrahydroxyxanthone, were synthesized from benzophenone precursors by Friedel-Crafts acylation and subsequent base-catalyzed cyclization to eliminate methanol. Both 3,4,6,7- and 2,3,6,7-tetrahydroxyxanthone tetraacetate showed potent anti-platelet aggregation effects on arachidonic acid-induced platelet aggregation. 3,4,6,7-Tetrahydroxyxanthone tetraacetate and 1,3,5,6-tetrahydroxyxanthone showed potent and significant anti-platelet aggregation effects on collagen-induced platelet aggregation.