Synthesis of Amaryllidaceae alkaloids, siculine, oxocrinine, epicrinine, and buflavine

Three crinane type of alkaloids isolated from Amaryllidaceae family were synthesized by taking advantage of the PIFA-mediated intramolecular p-p′ diphenol coupling reaction of norbelladine derivatives. Furthermore, buflavine was also prepared by using the p-p′ diphenol coupling followed by dienone–phenol rearrangement as a key step.