Biomimetic Domino Knoevenagel/Cycloisomerization Strategy for the Synthesis of Citridone A and Derivatives.

Studies on Knoevenagel condensations between conjugated dienals and 4-hydroxy-2-pyridone/quinolone-type 1,3-dicarbonyl equivalents led to the development of a simple one-pot strategy to access citridone A and related synthetic cyclopenta[]furopyridones/quinolones. The present work highlights the power of domino cascades in the synthesis of natural product frameworks and may help promote future studies on this promising new class of pyridone alkaloids.

Cycloisomerization of Conjugated Trienones and Isomeric 2H-Pyrans: Unified Strategy toward Cyclopenta[b]furans.

Conjugated trienones and isomeric 2H-pyrans were found to engage in a novel cycloisomerization cascade toward cyclopenta[b]furan derivatives. Knoevenagel chemistry and pericyclic reactions meet again to expand the polyene-carbonyl manifold.