Rapid Total Synthesis of (±)Trigonoliimine A via a Strecker/Houben–Hoesch Sequence

A novel synthetic route to the hexacyclic system of trigonoliimine A was accomplished in four steps from <i>N</i>-phthaloyl 6-OMe-tryptamine. Key reactions include a three-component Strecker-type reaction to fashion the two C–N bonds in the D ring and a subsequent Houben–Hoesch type cyclization to deliver the characteristic seven-membered C ring