Formal total synthesis of pseudopteroxale. Progress toward total synthesis of hamigeran B

Abstract

In the first chapter, a formal total synthesis of pseudopteroxazole is presented, highlightening an E-selective Horner-Emmons reaction, a Buchwald-Hartwig coupling, and a diastereoselective intramolecular Michael addition. In the second chapter, the effort toward synthesizing anti-viral natural product hamigeran B is summarized. Several routes to the core structure were shown separately, including those unexpected discoveries when pursuing those routes. Tius-Nazarov cyclization was first applied in synthesizing natural product; an efficient palladiumcatalyzed oxidative intramolecular carbocyclization was realized on an α-hydroxy enone for the first time; an interrupted Nazarov cyclization of a hydrolysis intermediate of dithiane was achieved.