Routes to 3-acyl-, 3-carboxamido- and polyhydroxylated flavones have b
een devised by application of isoxazole methodology and Heck-Stille co
uplings. Reductive ring opening of 3-alkoxyisoxazoles gives beta-keto
carboxamides in contrast with 3-alkoxy-2-isoxazolines, which give beta
-hydroxy esters.