Abstract:
The synthesis of dihydroquinoline-fused-canthines via intramolecular aza-Diels-Alder reaction between N-prenylated-1-formyl-9H--carbolines and substituted anilines in the presence of Lewis acid followed by oxidation is described. Additionally it has been found that the N-protected aldehyde in the presence of suitable catalyst (ZnBr2 or Yb (OTf)3) undergoes intramolecular carbonyl- ene reaction in diastereoselective fashion to afford syn- or anti-isomer of a new canthine derivative.
