Total synthesis of aritasone, cymbodiacetal and progress towards dihypoestoxide

Abstract

This thesis describes the synthetic studies towards dihypoestaxide, accompanied by total syntheses of aritasone and (+)-cymbodiacetal. These are all terpene derived natural products that share a common spirochroman core structure. The introduction details the isolation, biological significance and proposed biosynthesis of the aforementioned natural products, followed by a review of the previous work towards them. The key step in OUf synthesis is a heteTo-Diels-Alder dimerisation reaction of the corresponding monomeric exocyclic enane for the formation of a common tricyclic spirochroman core structure. The hetero-Diels-Alder cycloaddition reaction is reviewed. with special regard to its stereochemical outcomes, which suggest a preference for the endo-cyclOtiddition pathway in this reaction. The results and discussion section gives a detailed account of the preliminary studies undertaken to explore the hetero-Diels-Alder dimerisation. Our attempts to synthesise aritasone via the dimerisation of pinocarvone are described, which resulted in a total synthesis of aritasone and X -ray analysis confirmed the stereochemistry of the natural product.EThOS - Electronic Theses Online ServiceGBUnited Kingdo