An investigation toward the synthesis of the lindenane-type sesquiterpenoid monomer of Chlorahololide A using a Yamamoto rearrangement, intramolecular cyclopropanation reaction, 1,3-dipolar cyclization, and an intra- molecular Heck reaction gave the pivotal intermediate 20. This gives a practical synthetic route that could generate further natural products of the Chloranthaceae family.
The natural product,1,7-dimethoxy-2-hydroxyxanthone(1),isolated from Securidaca inappendiculate Hassk,has a potential in the treatment of erectile dysfunction due to its significant relaxation activity on rabbit Corpus cavernosum.However,the isolation of compound 1 is problematic because of its high similarity in structure to its analogs.In this paper,the first synthesis of 1 was reported featuring two key reactions:a copper-catalyzed coupling reaction and an intramolecular cyclization.