Document Type



Timo Ovaska

Publication Date



Frondosin D is a natural product generated by the marine sea sponge Dysidea frondosa that has a litany of documented medicinal effects, including acting as a potent anti-inflammatory, anti-HIV, and tumor suppressant agent. So far, the Ovaska lab methodology has successfully utilized a tandem 5-exo dig cyclization to form the core seven membered ring in three, A-C, of the five isoforms in the frondosin family. In addition to leveraging the reliability of this approach, two major ring construction sequences, A-D-B-C and D-C-B-A, have been explored as viable pathways in synthesis efforts of frondosin D. This present study investigated variations of the D-C-B-A approach, wherein modifications to both key tertiary alcohol and tricyclic ketone intermediates were performed in order to facilitate the installation of the A ring system to the remainder of the molecular scaffold. One of these attempts appeared to be successful in affording the tetracyclic skeleton of frondosin D. It is expected that the Ovaska lab will build off the progress associated with development of the structural core, in addition to exploring the advantages of other ring construction techniques, in order to chart an efficient route towards the total synthesis of natural product frondosin D.



The views expressed in this paper are solely those of the author.