Total synthesis of securinega alkaloids (-)-norsecurinine, (-)-niruroidine and (-)-flueggine A

A consecutive synthetic strategy was developed toward the total synthesis of securinega alkaloids. (-)-Norsecurinine was concisely assembled by addition of a methoxyallene to a ketone for efficient side-chain installation. Ring-closing metathesis was also utilized as a key step. The first total synthesis of (-)-niruroidine was achieved from (-)-norsecurinine in three steps, while the route to (-)-flueggine A featured a 1,3-dipolar cycloaddition to forge the core structure.