Skip to main content
eScholarship
Open Access Publications from the University of California

UC San Diego

UC San Diego Electronic Theses and Dissertations bannerUC San Diego

The enantioselective total synthesis of (+)-Symbioimine

  • Author(s): Born, Stephen Christopher
  • et al.
Abstract

(+)-Symbioimine is a marine-derived alkaloid isolated by Uemura in 2004 from a culture of Symbiodinium sp., a dinoflagellate that is a symbiont of the acoel flatworm Amphiscolops sp. This natural product has been found to inhibit osteoclastogenesis in the murine monocytic cell line RAW264 (EC₅₀ = 44 micrograms/mL), suggesting that either it or its analogues may offer a new opening to the development of preventative treatments for osteoporosis. In addition, it has been found to exhibit inhibition of Cycloxygenase (COX-2), suggesting possible use as an antiinflammatory. From a structural perspective, the bicyclic cyclohexenyl imine moiety is a unique feature endemic to several marine natural products. While it is postulated that these natural products undergo some version of the Diels-Alder reaction in their biosyntheses, there has yet to be an investigation that has yielded a general method for its incorporation. Herein I describe our investigation into and completion of the convergent, biomimetic, enantioselective total synthesis of (+)- Symbioimine, featuring an intramolecular, iminium- activiated Diels-Alder reaction that constructs the 6,6,6- tricyclic iminium framework as a single. Additionally, I will also report on our discoveries into the reactivity of various 2,3-dihydropyridine intermediates, the results of which may assist in the synthesis of the several other structurally similar natural products.

Main Content
Current View