Bio-inspired Total Synthesis of Twelve Securinega Alkaloids: Structural Reassignments of (+)-Virosine B and (-)-Episecurinol A

Abstract

The so-called Securinega alkaloids constitute a class of tetracyclic biologically active specialised metabolites isolated principally from subtropical plants belonging to the Phyllanthaceae family. Following a strategy based on alternative hypotheses for their biosynthesis, an easy and time-efficient divergent synthesis enabled access to twelve of those alkaloids featuring (neo)(nor)securinane skeletons. Moreover, this work permitted to reassign the absolute configurations of (+)-virosine B and (-)-episecurinol A.

Keywords: aldol reaction; alkaloids; biomimetic synthesis; natural products; total synthesis.