Oxygen insertion in Sesamum indicum furanofuran lignans. Diastereoselective syntheses of enzyme substrate analogues.

The furofuran lignans in sesame seed have an unusual oxygen insertion between their furan and aryl rings. In our continuing investigations on the isolation and characterization of the enzyme(s) involved, the diastereoselective syntheses of various substrate analogues for the oxygen insertion step were developed for future substrate specificity and inhibitor studies. This synthetic strategy also provided entry to so-called furofuranone epoxy-lignans, such as salicifoliol from Bupleurum sp., and acuminatolide from Helichrysum sp.