Synthetic studies toward the total synthesis of puraquinonic acid

Abstract

Puraquinonic acid 1, a fungal bioactive metabolite, has shown potential to cure Leukemia and is, therefore, an attractive target molecule to synthesize. The previous syntheses of this natural product have described the formation of the quaternary carbon center as one of the toughest steps in the synthesis. Consequently, we have developed an efficient enantioselective transformation of the key intermediate to a chiral molecule via a desymmetrization to introduce the quaternary carbon center. Finally, we attempted to apply this synthetic methodology toward the natural product synthesis. As a result, we successfully illustrated the construction of the bicyclic core structure of Puraquinonic acid 1 through a Lewis acid catalyzed Diel-Alder reaction with the designed cyclic dienophile and the test substrate, 2-methoxyfuran. With this promising transformation, we attempted to synthesize an ideal target diene bearing all the substituents of the right part of Puraquinonic acid 1 and their application to the synthesis.