Stereoselective Synthesis of Spirolactone Analogues of Pyrrolomorpholine Alkaloids.
Ami UchiyamaHikari OhtaYuya OgawaIkuo SasakiHideyuki SugimuraPublished in: The Journal of organic chemistry (2024)
The synthesis of a spirolactone analogue of xylapyrraside B 1 , a potent antioxidant agent, is described. The key step is the stereoselective formation of the spirolactone skeleton via the formal [3+2] annulation of the isopropylidene-protected glyceraldehyde and δ-methylene lactone, mediated by trifluoroborane etherate. This study addresses the stereoselective synthesis of pyrrolomorpholine spiroketal alkaloids, enabling the production of these bioactive compounds and their analogues.