Total synthesis of granditropone, grandirubrine, imerubrine, and isoimerubrine
Concise total syntheses of the naturally occurring tropoloisoquinolines grandirubrine (1), imerubrine (2), and isoimerubrine (3) are detailed. The regioselective total synthesis of grandirubrine (1) is based on the [4 + 2]cycloaddition reaction of the α-p