Popis: |
Two concise and complementary routes to the polycyclic alkaloid brevianamide A from readily available amino acid building blocks is presented. Key to the synthesis is the strategic use of a gold(I)-catalyzed cascade process that quickly assembles the characteristic pseudoindoxyl motif of the natural product along with the two adjacent quaternary centers in a single step. This sequence, which exemplifies the structural complexity that can be achieved with gold catalysis, allowed for the shortest and highest yielding synthesis of brevianamide A to date (4 steps LLS, 14% overall yield) |