Asymmetric construction of densely functionalized three-dimensional aza-tetracyclic scaffolds for drug discovery.

Asymmetric construction of densely functionalized three-dimensional aza-tetracyclic scaffolds were achieved by intramolecular Diels-Alder reaction of bicyclic precursors derived from L-tyrosine. Three substituents were systematically introduced into the developed scaffolds in various combinations, demonstrating their high utility in drug discovery.