Biomimetic total synthesis of proto-daphniphylline.

Proto-daphniphylline, the imputed biogenetic parent of the Daphniphyllum alkaloids, has been assembled in a biogenetically styled laboratory synthesis in which a pentacyclization process is the fundamental synthetic stratagem. This extraordinary transformation involves the formation of six (r-bonds under the influence of three elementary reagents-potassium hydroxide, anmnonia, and acetic acid. The facility of the process adds credibility to the previous speculation that a similar process is an important step in the biosynthesis of the Daphniphyllum alkaloids.