76013-33-7Relevant academic research and scientific papers
γ-Pyrone compounds. II: Synthesis and antiplatelet effects of tetraoxygenated xanthones
Lin,Liou,Ko,Teng
, p. 1109 - 1112 (2007/10/02)
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.
Studies in the Xanthone Series. Part 13. Structural and Synthetic Studies on Toxyloxanthone B
Cotterill, Phillip J.,Scheinmann, Feodor
, p. 2353 - 2357 (2007/10/02)
A re-consideration of the 1H n.m.r. data for toxyloxanthone B trimethyl ether and an unambiguous total synthesis both show that toxyloxanthone B has the 1,1-dimethylpyranoxanthone structure (1a) and not the 3,3-dimethylpyranoxanthone system (2) previously assigned.The synthesis is based on the preparation of 1,7-dihydroxy-3,5-dimethoxyxanthone (5) from cyclisation of a benzophenone precursor (3a) or (3b) and selective demethylations.A Claisen rearrangement of the 7-prop-2-ynyloxyxanthone (6) followed by cyclisation and methylation gives toxyloxanthone B trimethyl ether.
