Synthesis of fused pyran and arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)methane in ionic liquid

Promoted and mediated by an ionic liquid-[bmim][BF4], fused pyrans or arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)methanes were efficiently and selectively prepared from the reaction of aldehyde and 4-hydroxy-6-methyl-2-oxo-pyran with or without acetic anhydride. By using these novel procedures, pyrimidine nucleoside-fused pyran and arylbis(pyranon-3-yl)methane hybrids with potential biological activities were constructed.